(05-29-2020, 12:38 AM)TheOldPresbyope Wrote: @JonPike
As your alsacap output shows, your Schiit is reporting it can handle 32-bit material so moOde/MPD/ALSA will send it, but in a quick search of the InterWEB™, I see others saying it converts 32-bit material back down to 24-bit internally.
Why don't you ask Schiit?
Regards,
Kent
I may.. but that probably isn't part of the issue here. From data sheets, we know that the core DAC can handle up to 32/768, if set up for it, but the USB interface can handle a max of 32/192. The SPDIF input is limited to 24/192.
The issue seems to be in the software, someplace... in the parts that feed the audio devices, resample, bit pad, and apply filtering. I had thought it might be some config issue with the Schiit, but I dont think so now. The name dosen't appear in the quirks, it gets reported as it should, etc.
As Tim says, you have to figure what the different pieces along the way have as limitations. I found a mention in the history of the crossfeed, that it has a 192k limit, but in the above code there's a line saying max rate is 384? Looks like the guy who wrote it has been gone 5+ years and isn't available to ask.
What do you think, Tim? Maybe there's some kind of error handling in the main line audio stuff, for when you attempt to resample to something over what the stated device limit is, and the EQ blocks don't support and break it? The error msg sounds like its reporting not finding a (faster than exists) device.
Anyway, don't want to beat a dead horse, or even one that's just feeling poorly... Was hoping it might be an easy thing to find.
Overall conclusion, if you're using a Schiit Modi 3 (or any other dac that has limits?) and you want to resample and do some DSP, best keep it below the limit it should perform at.
