Consistent buzzing noise on all audio ports - EMI?

[aerothorn]

Hey all -

So after a long and arduous build, I've finally completed a PC that seems to be working hunky-dory with one exception.

I installed my Auzentech Forte card that I got a few years ago and wasn't able to use in the last build. It's a fantastic soundcard, but the original run had some sensitivity to EMI that would create buzzing noises; wrapping the bracket in electrical tape generally fixed it, and had on the last build before I took the card out. Here, it was back with a vengeance.

I figured it was an issue with the card, and while waiting on Auzentech support switched to the mobo's built-in audio...only to find the exact same phenomenon. The plugs are located on opposite ends of the case and there's even completely different drivers. The headphones in question worked fine on the previous computer, so it's definitely a system issue.

I'm assuming there's just a ton of EMI, but I'm not sure what would be causing it - I got a fairly nice PSU (Rosewill Capstone 550M). Are there any standard processes for tracking this down or otherwise resolving an issue like this? I would like to have decent sound on my PC

It's worth noting that it's fairly mild while the system is idle, and becomes quite loud when under load, which is why I'm thinking EMI.

 

[PanicMaster85]

well dont forget to install all the drivers for your sound card and the on board sound... also... when in use do you only use the card not like sound from card and then mic to onboard?

 

[aerothorn]

All drivers are installed.

Not sure what you mean by "mic to onboard," but I've tried using both the discrete sound card and front panel connected to mobo (not sound card).

Strangely, I've just discovering that connecting to the rear I/O panel generates no interference.

 

[PanicMaster85]

do you have the sound card application open? also have you tried reinstalling the drivers for the onboard sound?

 

[aerothorn]

I've tried re installing drives for both soundcard and onboard, but neither seems to do anything, nor does changing settings in the sound card application. Not even sure who I'd contact for support on this - could be the mobo, could be the power supply generating EMI. Not sure.

Also the rear I/O is now making noise too

 

[PanicMaster85]

huh so are you plugged into the back audio ports or the ones on the front of the case?

 

[aerothorn]

Both! That's the problem. If it was just one set of ports I'd figure it was an issue with that setup, but the problem is very active both on the discrete PCI-Express card (in the back) and on the front I/O panel (connected to the mobo, not the card). The problem is less present on the rear I/O panel, but still noticeable as a background noise.

In other words, I think it's safe to say it's not the ports themselves; something is flooding the entire system with interference. The only thing I can think of is that the power supply is somehow not properly shielded, since this PC is in the exact same location as my last PC, which has no such problems, so it's not environmental.

 

[PanicMaster85]

do you have any other psu's to test with maybe from another build?