On 07/07/2018 05:47 PM, Fons Adriaensen wrote:
Hello all,

Has anyone tried using multichannel USB audio on a Raspberry 3B+ ?

It seems to work perfectly (using zita-alsa-pcmi) with stereo cards.

When I try my RME Babyface (12 in, 12 out) in CC mode, the device
opens without problems, but then Alsa_pcmi::pcm_wait() times out
waiting for the poll fd to become ready. Timeout in pcm_wait() is
1000 milliseconds.

The same seems to happen with Jackd, which uses similar code.

Is there anything in the Pi's system or configuration that
excludes multichannel cards ?

Not that I'm aware of. I've used an older Pi2 with a Gigaport HD+ USB device (eight RCA outputs at 44k1) with usable results for 5.1, and my KODI-based media center plays 5.1 movie content over (albeit over HDMI) flawlessly without breaking a sweat, ever.

If your quality requirements are modest you might want to look at the AudioInjector Octo I²S sound card for the Pi. I have two from an early series with known manufacturing defects, but if the developer (a very open-sourcey hardware hacker guy that is generally very helpful) has managed to get his chinese manufacturer to ramp up the quality control, it might be an option.
I did a few measurements with this card a while ago:
http://forum.audioinjector.net/viewtopic.php?t=3090

I have never used a professional USB multichannel card on the Pi since I don't own one (still stuck with aging ExpressCard Multi- and MADIfaces). But I'm trying to borrow one for testing becaus I have a similar usecase in the near future...


All best,

Jörn


--
Jörn Nettingsmeier
Tuinbouwstraat 180, 1097 ZB Amsterdam, Nederland
Tel. +49 177 7937487

Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT
http://stackingdwarves.net
_______________________________________________
Linux-audio-dev mailing list
Linux-audio-dev@lists.linuxaudio.org
https://lists.linuxaudio.org/listinfo/linux-audio-dev

Reply via email to