06-06-2020, 05:36 AM
@normand
if you unplug any IN cables from your SMSL amp and there's no buzzing it means that your having the classic case of a 'ground' loop. The devices on their own have no fault as such. There are electronic countermeasures (pricey), cheap solutions used in automotive industry and some DIY solutions involving having a mains plug having just the EARTH wire connected (no NEUTRAL and LIVE wires) and experimentally connecting it to the GROUND of each device.
I suspect (correct me if I am wrong) that you use switch-mode power supplies to feed 5VDC to the RPi combos... try to make a test using linear PSU.
if you unplug any IN cables from your SMSL amp and there's no buzzing it means that your having the classic case of a 'ground' loop. The devices on their own have no fault as such. There are electronic countermeasures (pricey), cheap solutions used in automotive industry and some DIY solutions involving having a mains plug having just the EARTH wire connected (no NEUTRAL and LIVE wires) and experimentally connecting it to the GROUND of each device.
I suspect (correct me if I am wrong) that you use switch-mode power supplies to feed 5VDC to the RPi combos... try to make a test using linear PSU.
