Sega Genesis Model 1 Sound Problem

[brandman]

if you still have the broken adapter around, open it up and take a look at the filter capacitor inside. ive had a couple of 3 in one (nes/snes/genesis) adapters that would give buzzing in genesis audio. they also caused problems with the snes (powers on but doesnt boot) but oddly enough, worked fine for NES because that system has an internal filter capacitor (and a diode bridge, which explains why you can use any polarity on the adapter without harming it )
i opened them up and sure enough, the capacitors were blown. cheap garbage grade taiwanese caps

Wow, I'll take a look inside. Actually I was using it for my NES now, because I looked at the then NES adapter and it was the wrong wattage while the one I was using for the Genesis was the correct one. I haven't tried it out with the NES yet though.

[Hobie-wan]

Higher amperage rating on the power brick than the system requires is fine. The system will only pull what it needs. Like going from a 500 watt power supply in your PC to a 1000 watt one doesn't mean your PC is using that much power all the time. Just that it can if the devices in the PC need it. As noted, the NES is odd because the brick puts out AC and the console has another power setup inside to step down and rectify again.

For normal devices with a brick that puts out DC, just need to match the voltage and polarity. The brick's mA rating can be the same or higher than what the device needs.