Antipodes music servers use Linux native USB drivers. These drivers are 100% compatible with the USB Audio 2.0 Standard.
The situation for USB inputs on DACs is not so straightforward. What you need to ensure is that your DAC’s USB input is also compatible with the standard, but there are DAC manufacturers that focus more on the Windows and Mac markets that don’t do the work to ensure they completely comply with the industry standard.
If you have a question about the compatibility of your DAC to work with an Antipodes music server, then the best course of action is to ask the DAC manufacturer whether they are, or are not, compliant with the USB Audio 2.0 Standard. Antipodes is not able to speak on behalf of DAC manufacturers on this point, but we may be able to comment on whether we have had problems or not previously with a particular DAC.
Typically, DAC manufacturers that us XMOS USB inputs are compatible. Unfortunately a commonly used XMOS USB chip, the U8, has firmare bugs.
With all credit to Bart van der Laan of Kii Audio, we have identified the problem some users have had with using their DACs with Antipodes servers (and other servers with low-latency outputs). The U8 XMOS chip (used by several DACs in their USB input) had a firmware bug that meant that the DAC’s USB input could crash inelegantly and require restarting. This crash would occur when using Roon or MPD, between PCM tracks in a playlist, when going from a 44.1/16 track to a 44.1/24 track, or vice versa. There are a number of workarounds that can avoid the crash, but when we sent an Antipodes server to Kii Audio for testing, Bart identified the problem and posted the bug report on Github for XMOS.
If you have a DAC that has this problem, we suggest you contact your DAC manufacturer citing the link above, as this is the ideal way to address the problem. We have alerted Roon to this bug and the fix identified. This may not get you an immediate fix, so there are two workarounds you can use.
- You can use Roon’s DSP feature to upsample 44.1 sample rate files to say 88.2, and the different bit-depths are eliminated as the files will be re-dithered to the maximum bit-depth your DAC can handle, on the fly.
- You can continue to use Roon as your server app but switch to using Squeezelite or HQPlayer Embedded as your renderer.