TPA3116D2 Breeze audio 2.1 amp intermittent hum

Thanks Jensen.
the whole case doesn't seem to be grounded at all.
I'm using a laptop power supply if that at all matters.
What I i did just notice is that when one of my appliances was working i got some hum.

As in white goods? Fridge etc? If so you might try a ferrite core and/or a conditioned trailing socket (if that's the right phrase...).