Static with amp

Hi,
currently trying to build a simple speaker system (input source will be a pi, but i'm not even that far yet, so doesn't really matter) and struggling with static.
The system should be a "costant on" wifi speaker controlled by the pi, so constant static is not ideal.

Observations:
PSU, AMP and speakers results in some static noise.
adding a DAC to the amp (which later will connect to the pi) adds a lot more static
and when i touch the dac cable static increases even more.

Parts:
Amp: TPA3110 (from aliexpress)
Dac: cheap usb c one from amazon
Speakers: JVC CS-J420X
Psu: cheap 12V one from aliexpress

have attached pictures of the setup and videos with static.

since I'm fairly new to this (and also don't have different parts to try different combinations) I'd love some input for what might cause this and how to remediate it.
 

Attachments

  • more static when touching dac.mp4
    10.3 MB
  • static with dac.mp4
    9.2 MB
  • setup with dac.jpg
    setup with dac.jpg
    422.4 KB · Views: 24
  • static no dac.mp4
    8.6 MB
  • setup no dac.jpg
    setup no dac.jpg
    441.1 KB · Views: 24
Shorting the input to the amp is fundamental to any noise test. I use a RCA cable and short the pin to the ring of the free end with an alligator clip lead. No static on the P.S., you need a noise free source.
If you have a 12 v battery, or a cigarette lighter plug for your car going to two wires, and a couple of alligator clip leads, you can eliminate the 12 v P.S. and see if the static goes away. If it does, the PS is bad. If not, the TPA3110 is bad.
 
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