I have the same issue :
I have two squeezlites : one with Hifiberry Amp+ and one with an usb sound card.
And every about 6 hours, the squeezelite with usb card stop working and I heard „dududududududu“.
To fix that, I have to restart the squeezelite service (I do it with a ssh connection, I’ve never try with the web interface).
I changed the power supply but I have the same issue.
I’ve used this usb card fo a couple of years with mpd and with this power supply and I’ve never had this problem.
Any idea ?