"TypeError: cannot convert undefined to object" in VoskletTransferer

[tdcook]

Sometimes, VoskletTransferer will throw a TypeError: cannot convert undefined to object exception immediately after initialization. It won't always happen right away, but usually will after a few reloads. It seems there is a race condition between the connection of the source and processor nodes and the execution of VoskletTransferer's process method.

The error is being thrown here:

https://github.com/msqr1/Vosklet/blob/76aedbdfee862de8a734a3a4f09ffb82eeaf50da/src/wrapper.js#L11

Adding a falsiness check here should fix it:

const data = inputs[0][0]
if (!data) return true
this.buffer.set(data, this.count * 128)

[msqr1]

Ngl, I never encounter this issue when testing (where I reload a zillion times). What browser are you using?

Thanks for pointing this out, I'll fix it ASAP!

[tdcook]

I have tried Chrome and Firefox, all on a Linux machine with a USB microphone attached. I suspect it only crops up on certain systems.

[msqr1]

Can you try unplugging the USB microphone, if you are encountering issue from the microphone recognition? Or is it just straight from startup, not doing anything yet?

[tdcook]

It happens right on startup, before any recognition starts. I have only seen it happen there, never after a successful startup.

[msqr1]

This path of code is quite hot, can you try unplugging the USB microphone to see? I tried many times to see if it would pop up, but it wouldn't. Can you try if the USB microphone was the problem? Maybe it messed with the AudioContext?

[tdcook]

Well, if I remove the USB microphone from that machine, I won't have any microphone input to use. Instead I tested it on two laptops using their built-in microphones:

Framework Laptop 16 (Fedora Linux 40): Firefox 126 repros inconsistently. Chrome 125 repros more consistently but occasionally works.

Surface Pro 4 (Windows 10): Firefox 126 repros inconsistently. Edge reproed once on the very first try but never reproed again.

According to the spec the inputs array for a source can be empty if the source node is not "actively processing". Perhaps there is, on some OS/browser combinations, a moment after initialization where the microphone stream node is not actively processing.

[msqr1]

@tdcook Can you recheck (latest commit on main)?

[tdcook]

Looks good, thanks!