Pulseaudio backend does not work reliable

[klingtnet]

Pulseaudio outputs only a single buffer of audio and then stops the output. This issue occurs for other users as well (#6). Getting pulseaudio's debug output is not as straight-forward as one might think, at least not on Arch Linux machines running Gnome 3. To get the debug log use the following steps:

• add autospawn=no to your ~/.config/pulse/client.conf (or /etc/pulse/client.conf, but the former one is preferred)
• disable the systemd user service (this is not mentioned in the Arch Wiki): systemctl --user stop pulseaudio
• maybe it's necessary to stop the socket too: systemctl --user top pulseaudio.socket to prevent pa from respawning
• kill leftover daemons: killall pulseaudio
• run with debug output: pulseaudio -vvvvv --log-level=debug --log-time --daemonize=no

Running cargo run --release --example sine produced the following log output:

   3.149|   0.000) D: [pulseaudio] module-augment-properties.c: Looking for .desktop file for sine
(   3.149|   0.000) D: [pulseaudio] protocol-native.c: Client enabled srbchannel.
(   3.150|   0.000) D: [pulseaudio] module-stream-restore.c: Not restoring device for stream sink-input-by-application-name:rsoundio-example, because already set to 'alsa_output.pci-0000_00_1b.0.analog-stereo'.
(   3.150|   0.000) D: [pulseaudio] module-intended-roles.c: Not setting device for stream sine, because already set.
(   3.150|   0.000) D: [pulseaudio] sink-input.c: Negotiated format: pcm, format.sample_format = "\"float32le\""  format.rate = "48000"  format.channels = "2"  format.channel_map = "\"front-left,front-right\""
(   3.150|   0.000) I: [pulseaudio] sink-input.c: Trying to change sample rate
(   3.150|   0.000) I: [pulseaudio] sink-input.c: Rate changed to 48000 Hz
(   3.150|   0.000) I: [pulseaudio] module-stream-restore.c: Restoring mute state for sink input sink-input-by-application-name:rsoundio-example.
(   3.150|   0.000) D: [pulseaudio] module-suspend-on-idle.c: Sink alsa_output.pci-0000_00_1b.0.analog-stereo becomes busy, resuming.
(   3.150|   0.000) D: [pulseaudio] module-suspend-on-idle.c: Sink alsa_output.pci-0000_00_1b.0.analog-stereo becomes idle, timeout in 5 seconds.
(   3.150|   0.000) I: [pulseaudio] resampler.c: Forcing resampler 'copy', because of fixed, identical sample rates.
(   3.150|   0.000) D: [pulseaudio] resampler.c: Resampler:
(   3.150|   0.000) D: [pulseaudio] resampler.c:   rate 48000 -> 48000 (method copy)
(   3.150|   0.000) D: [pulseaudio] resampler.c:   format float32le -> s32le (intermediate float32le)
(   3.150|   0.000) D: [pulseaudio] resampler.c:   channels 2 -> 2 (resampling 2)
(   3.150|   0.000) D: [pulseaudio] memblockq.c: memblockq requested: maxlength=33554432, tlength=0, base=8, prebuf=0, minreq=1 maxrewind=0
(   3.150|   0.000) D: [pulseaudio] memblockq.c: memblockq sanitized: maxlength=33554432, tlength=33554432, base=8, prebuf=0, minreq=8 maxrewind=0
(   3.150|   0.000) I: [pulseaudio] sink-input.c: Created input 0 "sine" on alsa_output.pci-0000_00_1b.0.analog-stereo with sample spec float32le 2ch 48000Hz and channel map front-left,front-right
(   3.150|   0.000) I: [pulseaudio] sink-input.c:     media.name = "sine"
(   3.150|   0.000) I: [pulseaudio] sink-input.c:     application.name = "rsoundio-example"
(   3.150|   0.000) I: [pulseaudio] sink-input.c:     native-protocol.peer = "UNIX socket client"
(   3.150|   0.000) I: [pulseaudio] sink-input.c:     native-protocol.version = "30"
(   3.150|   0.000) I: [pulseaudio] sink-input.c:     application.process.id = "23551"
(   3.150|   0.000) I: [pulseaudio] sink-input.c:     application.process.user = "andreas"
(   3.150|   0.000) I: [pulseaudio] sink-input.c:     application.process.host = "elitebook"
(   3.150|   0.000) I: [pulseaudio] sink-input.c:     application.process.binary = "sine"
(   3.150|   0.000) I: [pulseaudio] sink-input.c:     application.language = "C"
(   3.150|   0.000) I: [pulseaudio] sink-input.c:     window.x11.display = ":1"
(   3.150|   0.000) I: [pulseaudio] sink-input.c:     application.process.machine_id = "ce8d58fbb2eb4fcaafacb55ad232bcbc"
(   3.150|   0.000) I: [pulseaudio] sink-input.c:     application.process.session_id = "c2"
(   3.150|   0.000) I: [pulseaudio] sink-input.c:     module-stream-restore.id = "sink-input-by-application-name:rsoundio-example"
(   3.150|   0.000) I: [pulseaudio] protocol-native.c: Requested tlength=2000,00 ms, minreq=20,00 ms
(   3.150|   0.000) D: [pulseaudio] protocol-native.c: Traditional mode enabled, modifying sink usec only for compat with minreq.
(   3.150|   0.000) D: [pulseaudio] protocol-native.c: Requested latency=1960,00 ms, Received latency=1960,00 ms
(   3.150|   0.000) D: [pulseaudio] memblockq.c: memblockq requested: maxlength=4194304, tlength=768000, base=8, prebuf=0, minreq=7680 maxrewind=0
(   3.150|   0.000) D: [pulseaudio] memblockq.c: memblockq sanitized: maxlength=4194304, tlength=768000, base=8, prebuf=0, minreq=7680 maxrewind=0
(   3.150|   0.000) I: [pulseaudio] protocol-native.c: Final latency 3960,00 ms = 1960,00 ms + 2*20,00 ms + 1960,00 ms
(   3.150|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Latency set to 1960,00ms
(   3.150|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: hwbuf_unused=15360
(   3.150|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: setting avail_min=95041
(   3.150|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Requesting rewind due to latency change.
(   3.150|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Requested volume: front-left: 29777 /  45% / -20,56 dB,   front-right: 29777 /  45% / -20,56 dB
(   3.150|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Got hardware volume: front-left: 29899 /  46% / -20,45 dB,   front-right: 29899 /  46% / -20,45 dB
(   3.150|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Calculated software volume: front-left: 65269 / 100% / -0,11 dB,   front-right: 65269 / 100% / -0,11 dB (accurate-enough=yes)
(   3.150|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: Volume not changing
(   3.150|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Requested to rewind 768000 bytes.
(   3.150|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Limited to 733768 bytes.
(   3.150|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: before: 91721
(   3.150|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: after: 91721
(   3.150|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Rewound 733768 bytes.
(   3.150|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: Processing rewind...
(   3.150|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: latency = 1105
(   3.150|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink-input.c: Have to rewind 733768 bytes on render memblockq.
(   3.150|   0.000) D: [alsa-sink-92HD81B1X5 Analog] source.c: Processing rewind...
(   3.152|   0.002) D: [alsa-sink-92HD81B1X5 Analog] protocol-native.c: Requesting rewind due to end of underrun.
(   3.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] protocol-native.c: Requesting rewind due to end of underrun.
(   3.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink-input.c: Requesting rewind due to uncorking
(   3.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Requested to rewind 768000 bytes.
(   3.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Limited to 751240 bytes.
(   3.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: before: 93905
(   3.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: after: 93905
(   3.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Rewound 751240 bytes.
(   3.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: Processing rewind...
(   3.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: latency = 1215
(   3.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] source.c: Processing rewind...
(   3.153|   0.000) D: [pulseaudio] module-suspend-on-idle.c: Sink alsa_output.pci-0000_00_1b.0.analog-stereo becomes busy, resuming.
(   3.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] protocol-native.c: Implicit underrun of 'sine'
(   3.155|   0.002) D: [alsa-sink-92HD81B1X5 Analog] protocol-native.c: Requesting rewind due to rewrite.
(   3.155|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Requested to rewind 735784 bytes.
(   3.155|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Limited to 735784 bytes.
(   3.155|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: before: 91973
(   3.155|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: after: 91973
(   3.155|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Rewound 735784 bytes.
(   3.155|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: Processing rewind...
(   3.155|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: latency = 41383
(   3.155|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink-input.c: Have to rewind 735784 bytes on render memblockq.
(   3.155|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink-input.c: Have to rewind 735784 bytes on implementor.
(   3.155|   0.000) D: [alsa-sink-92HD81B1X5 Analog] source.c: Processing rewind...
(   3.155|   0.000) D: [alsa-sink-92HD81B1X5 Analog] protocol-native.c: Implicit underrun of 'sine'
(   4.432|   1.276) D: [alsa-sink-92HD81B1X5 Analog] protocol-native.c: Requesting rewind due to rewrite.
(   4.432|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Requested to rewind 768000 bytes.
(   4.432|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Limited to 751304 bytes.
(   4.432|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: before: 93913
(   4.432|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: after: 93913
(   4.432|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Rewound 751304 bytes.
(   4.432|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: Processing rewind...
(   4.432|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: latency = 1233
(   4.432|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink-input.c: Have to rewind 751304 bytes on render memblockq.
(   4.432|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink-input.c: Have to rewind 751304 bytes on implementor.
(   4.432|   0.000) D: [alsa-sink-92HD81B1X5 Analog] source.c: Processing rewind...
(   5.097|   0.664) I: [pulseaudio] module-suspend-on-idle.c: Source alsa_input.pci-0000_00_1b.0.analog-stereo idle for too long, suspending ...
(   5.097|   0.000) D: [pulseaudio] source.c: Suspend cause of source alsa_input.pci-0000_00_1b.0.analog-stereo is 0x0004, suspending
(   5.097|   0.000) I: [alsa-source-92HD81B1X5 Analog] alsa-source.c: Device suspended...
(   5.097|   0.000) D: [pulseaudio] module-udev-detect.c: /dev/snd/controlC2 is accessible: yes
(   5.097|   0.000) D: [pulseaudio] module-udev-detect.c: Resuming all sinks and sources of card alsa_card.pci-0000_00_1b.0.
(   5.713|   0.615) D: [alsa-sink-92HD81B1X5 Analog] protocol-native.c: Requesting rewind due to rewrite.
(   5.713|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Requested to rewind 768000 bytes.
(   5.713|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Limited to 751368 bytes.
(   5.713|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: before: 93921
(   5.713|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: after: 93921
(   5.713|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Rewound 751368 bytes.
(   5.713|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: Processing rewind...
(   5.713|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: latency = 997
(   5.713|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink-input.c: Have to rewind 751368 bytes on render memblockq.
(   5.713|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink-input.c: Have to rewind 751368 bytes on implementor.
(   5.713|   0.000) D: [alsa-sink-92HD81B1X5 Analog] source.c: Processing rewind...
(   6.153|   0.439) D: [alsa-sink-92HD81B1X5 Analog] protocol-native.c: Requesting rewind due to rewrite.
(   6.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink-input.c: Requesting rewind due to corking
(   6.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Requested to rewind 768000 bytes.
(   6.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Limited to 583368 bytes.
(   6.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: before: 72921
(   6.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: after: 72921
(   6.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Rewound 583368 bytes.
(   6.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: Processing rewind...
(   6.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: latency = 1062
(   6.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink-input.c: Have to rewind 583368 bytes on render memblockq.
(   6.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink-input.c: Have to rewind 583368 bytes on implementor.
(   6.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] source.c: Processing rewind...
(   6.155|   0.001) D: [pulseaudio] module-suspend-on-idle.c: Sink alsa_output.pci-0000_00_1b.0.analog-stereo becomes idle, timeout in 5 seconds.
(   7.153|   0.998) D: [alsa-sink-92HD81B1X5 Analog] sink-input.c: Requesting rewind due to uncorking
(   7.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Requested to rewind 768000 bytes.
(   7.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Limited to 751816 bytes.
(   7.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: before: 93977
(   7.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: after: 93977
(   7.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Rewound 751816 bytes.
(   7.153|   0.000) D: [pulseaudio] module-suspend-on-idle.c: Sink alsa_output.pci-0000_00_1b.0.analog-stereo becomes busy, resuming.
(   7.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: Processing rewind...
(   7.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: latency = 1057
(   7.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] source.c: Processing rewind...
(   7.156|   0.002) D: [alsa-sink-92HD81B1X5 Analog] protocol-native.c: Requesting rewind due to rewrite.
(   7.156|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Requested to rewind 752168 bytes.
(   7.156|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Limited to 751016 bytes.
(   7.156|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: before: 93877
(   7.156|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: after: 93877
(   7.156|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Rewound 751016 bytes.
(   7.156|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: Processing rewind...
(   7.156|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: latency = 1118
(   7.156|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink-input.c: Have to rewind 751016 bytes on render memblockq.
(   7.156|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink-input.c: Have to rewind 751016 bytes on implementor.
(   7.156|   0.000) D: [alsa-sink-92HD81B1X5 Analog] source.c: Processing rewind...
(   8.430|   1.273) D: [alsa-sink-92HD81B1X5 Analog] protocol-native.c: Requesting rewind due to rewrite.
(   8.430|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Requested to rewind 768000 bytes.
(   8.430|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Limited to 751368 bytes.
(   8.430|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: before: 93921
(   8.430|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: after: 93921
(   8.430|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Rewound 751368 bytes.
(   8.430|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: Processing rewind...
(   8.430|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: latency = 1810
(   8.430|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink-input.c: Have to rewind 751368 bytes on render memblockq.
(   8.430|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink-input.c: Have to rewind 751368 bytes on implementor.
(   8.430|   0.000) D: [alsa-sink-92HD81B1X5 Analog] source.c: Processing rewind...
(   9.711|   1.281) D: [alsa-sink-92HD81B1X5 Analog] protocol-native.c: Requesting rewind due to rewrite.
(   9.711|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Requested to rewind 768000 bytes.
(   9.711|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Limited to 751336 bytes.
(   9.711|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: before: 93917
(   9.712|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: after: 93917
(   9.712|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Rewound 751336 bytes.
(   9.712|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: Processing rewind...
(   9.712|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: latency = 1235
(   9.712|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink-input.c: Have to rewind 751336 bytes on render memblockq.
(   9.712|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink-input.c: Have to rewind 751336 bytes on implementor.
(   9.712|   0.000) D: [alsa-sink-92HD81B1X5 Analog] source.c: Processing rewind...
(  10.153|   0.441) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: hwbuf_unused=0
(  10.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: setting avail_min=95041
(  10.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Requested volume: front-left: 29777 /  45% / -20,56 dB,   front-right: 29777 /  45% / -20,56 dB
(  10.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Got hardware volume: front-left: 29899 /  46% / -20,45 dB,   front-right: 29899 /  46% / -20,45 dB
(  10.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Calculated software volume: front-left: 65269 / 100% / -0,11 dB,   front-right: 65269 / 100% / -0,11 dB (accurate-enough=yes)
(  10.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: Volume not changing
(  10.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Requested to rewind 768000 bytes.
(  10.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Limited to 582696 bytes.
(  10.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: before: 72837
(  10.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: after: 72837
(  10.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Rewound 582696 bytes.
(  10.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: Processing rewind...
(  10.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] sink.c: latency = 1394
(  10.153|   0.000) D: [alsa-sink-92HD81B1X5 Analog] source.c: Processing rewind...
(  10.154|   0.001) D: [pulseaudio] module-suspend-on-idle.c: Sink alsa_output.pci-0000_00_1b.0.analog-stereo becomes idle, timeout in 5 seconds.
(  10.155|   0.000) D: [pulseaudio] module-suspend-on-idle.c: Sink alsa_output.pci-0000_00_1b.0.analog-stereo becomes idle, timeout in 5 seconds.
(  10.155|   0.000) D: [pulseaudio] core.c: Hmm, no streams around, trying to vacuum.
(  10.155|   0.000) I: [pulseaudio] sink-input.c: Freeing input 0 "sine"
(  10.155|   0.000) I: [pulseaudio] client.c: Freed 6 "rsoundio-example"
(  10.155|   0.000) I: [pulseaudio] protocol-native.c: Connection died.
(  15.155|   4.999) I: [pulseaudio] module-suspend-on-idle.c: Sink alsa_output.pci-0000_00_1b.0.analog-stereo idle for too long, suspending ...
(  15.155|   0.000) D: [pulseaudio] sink.c: Suspend cause of sink alsa_output.pci-0000_00_1b.0.analog-stereo is 0x0004, suspending
(  15.157|   0.001) I: [alsa-sink-92HD81B1X5 Analog] alsa-sink.c: Device suspended...
(  15.157|   0.000) D: [pulseaudio] core.c: Hmm, no streams around, trying to vacuum.
(  15.158|   0.000) D: [pulseaudio] module-udev-detect.c: /dev/snd/controlC2 is accessible: yes
(  15.158|   0.000) D: [pulseaudio] module-udev-detect.c: Resuming all sinks and sources of card alsa_card.pci-0000_00_1b.0.

[klingtnet]

The pulseaudio stream works when pavucontrol runs besides the sine example. This is strange. Can somebody reproduce this @ul?

Here is a small video proof (I can't record audio with gnome's default screencaster).

[ul]

Yes, I confirm that weirdness! The example works with pavucontrol running on my system too, and doesn't work w/o it!

[klingtnet]

The original sine example writes always max_frame_count frames, which does indeed help a bit. I've updated the example in the master branch 0e6f0f8 to write max_frame_count frames, too. The output is still distorted, even though it now outputs a continuous signal.