Problems streaming Spotify on Yamaha A-S801

Here are the versions of the included components:

Pi 3 Model B+
MusicBox - v0.7.0 Release Candidate 7
Yamaha A-S801

Connected through Yamaha USB internal DAC.

I have problems streaming spotify music trough the amplifier. The problems started when I disabled the
“Downsample USB” button. From the logs it seems that the amplifier is recognized:

Do not see any particular error in the logs, but may be I don’t know where to look in.

I tried some radio stream. At first nothing happened but after 5 minutes, when I was doing something else suddenly music started playing.

Do you have any idea where to look for the problem?