So I'm working on a project of mine to integrate a power amp into my comp and run it off the PSU. The amp is this 25watt x2 by parts express: http://www.parts-express.com/pe/showdetl.cfm?partnumber=320-332
So here is my dilemma: it works, but there is lots of noise. Little more detail first though. I currently have it wires to run off pin 1 and pin 2 (12v and ground) from a 4 pin molex connection. The input is a RCA to 3.5mm headphone jack. I've used this connection on my Marantz 2325 with no issues, so I know the cable is good, and even tested it against another one. The power adapter is solid with a good connection that I made myself.
What at gets me on this though is that the static is only present when I use a computer PSU and connect it to my PC's headphone jack (ASUS crosshairs V Formula Z motherboard). If I use my laptops power supply, and connect it to the PC audio, there is no noise. If I use my PC's power supply, and connect the amp to my phone, again, no noise. However, PC power supply and PC audio means noise. I even tried another power supply to simply power the amp while my computer ran on its own PSU, and again, noise was present.
I'm im thinking it might be a grounding issue with the PSU on the desktops that won't let this work, or perhaps even the audio on the ROG motherboard is still dirty, and putting it with a PSU which may also have a dirty signal is only adding to the matter.
Im at at a loss here. Any ideas?