[PROBLEM] RPi4/Mood or RME ADI-2 FS problem?

[Tim Curtis]

The information in that link refers to Mac OS X operating system and not RaspiOS Linux on a Pi which is what moOde uses. 

You should ask the RME developer in that thread whether they test/support RaspiOS Linux on a Raspberry Pi and if they do then which Linux kernel version is required. They may only test and support Mac and Windows.

In any case they show the following MPD config section from a Mac which specifies the OSX output plugin. This plugin uses Apple's Core Audio API. https://mpd.readthedocs.io/en/stable/plugins.html#osx. moOde uses Linux ALSA API https://mpd.readthedocs.io/en/stable/plu...lsa-plugin. which is completely different. 

Also note that dop "yes" is specified which indicates the device probably only supports DoP and not Native DSD. This means that the USB interface provided by the operating system has to support a PCM rate of 705.6K

Code:

audio_output {
type "osx"
device "ADI-2 DAC (XXXXX)" # XXXX is the serial number
dop "yes"
hog_device "true"
name "RME ADI-2 DAC FS"
mixer_type "none"
}

You can check which sample rates and formats were reported by the device to Linux by running the command below.

Code:

moodeutl -F

Here is the output showing what my Revolution DAC reports. Note the 705.6 sample rate and DSD-U32_BE format. That format indicates Native DSD bitstream is supported by the DAC.

Code:

pi@rp1:~ $ moodeutl -F
*** Scanning for playback devices ***
.
.
.
Card 2, ID `Revolution', name `Revolution'
 Device 0, ID `USB Audio', name `USB Audio', 1 subdevices (1 available)
   2 channels, sampling rate 44100..705600 Hz
   Sample formats: S16_LE, S32_LE, SPECIAL, DSD_U32_BE
   Buffer size range from 16 to 262144
   Period size range from 8 to 131072

     Subdevice 0, name `subdevice #0'
pi@rp1:~ $