Not quite. The 'obvious if you know how' part is that Volumio's brutefir3 plugin expects the coefficients in a wav file, and 'silently' fails if you supply them in a wav file which is what Daphile uses and PORC outputs. The plugin also fails 'silently' with the Forte as the output device - there's a problem configuring the channel count which may be because the Forte is a 4 channel device not a 2 channel one. Disable the plugin and playback is fine. I say 'silently' because the web gui gives no indication that restarting BruteFIR has failed, just a green box saying it's restarting when you change the config. If you ssh in and check the log with
you get to see the errors when it fails to start. I may be able to get it working by editing the config template
Code:
/data/plugins/audio_interface/brutefir/brutefir.conf.tmpl
but it's proving to be more work that Daphile was.
My other USB interface is a lowly UCA202 which only does 16 bit 44.1kHz. With the example configs, and after dropping the sample rate and format so that BruteFIR would actually start, it plays. There were no pops when playing a couple of the high def L2 samples. mpd was at ~17% cpu, and the 2 brutefir.real processes were ~7% each, so it does appear to be doing more than just passthrough. How often would you expect pops, or do they not occur at such low sample rates?