29 Mar
2022
29 Mar
'22
4:03 a.m.
Michael Jarosch <riotsound(a)riotmusic.de> writes:
It's me, again!
Using a realtime kernel, I struggled with xruns on my Focusrite
Scarlett 2i4 (1st gen) and just wasn't able to work it out. Guess, I
didn't manage to include the device into rtirq's list of interrupts
with high priority…
Surprisingly, using a standard debian kernel solved it. Still, I would
love to understand, how to configure rtirq to make a usb audio
standard device just work… I ended up setting the interrupt numbers
[16,23] to RTIRQ_NAME_LIST without any success on the xrun front. But
maybe I should have done anything else? I configured my system doing
all the things mentioned in
https://wiki.linuxaudio.org/wiki/system_configuration AND verified
this and more with the rtcqs scripts.
The linux-show-player issue is also persistent…
Which sample rate, which period size and count? Personally I have found
that using a period size of the form 3*2^n rather than 2^n can
surprisingly improve results at 48kHz or 96kHz of sampling frequency,
likely due to the timer interval becoming better expressible in terms of
system ticks and/or milliseconds.
That can lead to a period size of 256 being problematic and a size of 48
samples working fine, depending on the device and drivers in question.
--
David Kastrup