Cannot write control 'numid=11,iface=HWDEP,name='DDS''

[rubin55]

When running alsactl restore on an RME HDSPe AIO Pro (using the snd-hdspe kernel module), I get the following error:

# alsactl restore -U
Found hardware: "HDSPe" "RME HDSPe" "" "0x0000" "0x0000"
Hardware is initialized using a generic method
alsactl: set_control:1494: Cannot write control 'numid=11,iface=HWDEP,name='DDS'' : Invalid argument

This seems to prevent systemd's alsa-restore oneshot from working, although I don't really understand why; running alsactl store/restore -U from command line shows the same error, but does store/restore volume levels. The same via systemd, logs the errors in systemd status alsa-restore but volume levels are never restored.