TPA3116D2 Breeze audio 2.1 amp intermittent hum

[aussiebuddha]

Hi All
I've had this amp for a while, and sometimes i get a hum for no apparent reason.
I've tried changing the power supply, but doesn't seem to be the problem.

When i touch the case, sometimes the hum stops.

What can the problem be?

thanks

 

[Jensen567]

Is the case connected to ground? On all of the potentiometers, it can help to ground the front metal piece there also.

 

[aussiebuddha]

Is the case connected to ground? On all of the potentiometers, it can help to ground the front metal piece there also.

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.

 

[Jerms]

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...).