Squeezelite on PI3, interruptions every ~5 secs

Hi there,

I want to use a PI3 connected to my audio receiver as a squeezelite player.
So far it is working if I start with only: squeezelite -o default:CARD=ALSA -s 192.168.1.23

However, every 5 seconds sound shuts off and seems to start over (volume goes from low to high) - what did I miss here?

Thank you!