search

raspberrypi / linux

Kernel source tree for Raspberry Pi-provided kernel builds. Issues unrelated to the linux kernel should be posted on the community forum at https://forums.raspberrypi.com/
Other
11.17k stars 5.01k forks source link

PI3B+: Playback from network share via eth0 results in garbled sound #2454

Closed volumio closed 6 years ago

volumio commented 6 years ago

With kernel 4.14.26-v7+, playing flac files from SMB shares via ethernet to USB DAC results in garbled sound (dropping packets?). The very same files, on the very same configuration play spotless via wlan0. Probably the same root cause as https://github.com/raspberrypi/linux/issues/2449

I'm available for testing

popcornmix commented 6 years ago

Does it work on a Pi3 using 4.14.26-v7+?

volumio commented 6 years ago

Yes, works flawless

popcornmix commented 6 years ago

@P33M any ideas?

P33M commented 6 years ago

Can you upload a waveform capture?

Make a FLAC file with a low-frequency sinewave - 440Hz or so - play it via the USB DAC - and capture a .wav file using line-in on a PC/laptop?

Also, do you get the same result when playing back via the onboard analogue port?

volumio commented 6 years ago

Here are the test results: Created 2 WAV files: 32\192khz and 32\384khz with a sine wave of 440Hz.

Results: Wifi -> USB DAC = OK Wifi -> Analog out = OK LAN -> USB DAC = Issues LAN -> Analog out = OK

Those are the captures of both files in the LAN to USB DAC situation: http://repo.volumio.org/Volumio2/tests-pi3b%2B/test-440-192-lan-usb.wav http://repo.volumio.org/Volumio2/tests-pi3b%2B/test-440-384-lan-usb.wav

With LAN I mean that the files are stored on a NAS and shared via SMB, the PI is conneted to network with gigabit ethernet.

If it can be useful, see the final part of the article for a bit of context: https://volumio.org/raspberry-pi-3-b-plus-audio-review/

P33M commented 6 years ago

As a test, what happens if you play the FLAC file from SD storage (i.e. locally) and then simultaneously run an iperf network bandwidth test? I would expect it to be garbled in the same manner.

volumio commented 6 years ago

No, running iperf while playing the 384\32 bit wav from SD Card produces no garble whatsoever. The command I am launching is iperf -c IPADDR

volumio commented 6 years ago

@P33M @popcornmix FIY A little bit better with 4.14.29 but still get dropouts

P33M commented 6 years ago

Quite probably related: https://www.raspberrypi.org/forums/viewtopic.php?f=63&t=208512&start=50#p1292589

It does not appear to be specific to audio - RX packet drops/line drops can be seen with e.g. rsync.

P33M commented 6 years ago

@volumio there have been multiple low-level fixes to Ethernet on 3B+. Please retest and report back.

volumio commented 6 years ago

@P33M sure, I'll let you know asap

volumio commented 6 years ago

@P33M Confirm that I do not hear any glitches now, when playing via eth. Seems to be fixed then

JamesH65 commented 6 years ago

Closing this issue as questions answered/issue resolved.