I'm having an issue with a high-pitched sound coming from my computer, which also seems to be transmitted to my home theater receiver and speakers.
I have a stereo mini-jack-to-RCA cable going from my motherboard headphone/line-out jack to a plate on my wall with RCA jacks. Behind that, I have RG6 coax cable running thru my attic to another wall plate behind my TV and receiver, with another set of RCA cables from the wall plate to the receiver. I can only hear the high-pitched sound through my center channel speaker.
The same sound can be heard from inside my tower case, and I think it's the power supply, but I'm not 100% sure. I'm pretty sure it's not a ground-loop issue, which I was told is more like a low hum than a high-pitched sound. To be sure I tried a set of ground-isolating RCA cables, on both ends of the room (to the receiver and to the computer), and neither location helped.
This is a system I built back in June 2006. Details are as follows:
- Intel D945Gnt motherboard
- Antec SmartPower 2.0 500W power supply
- Pentium D 3.2 GHz dual-core processor
- 2 GB RAM
- PNY nVIDIA Quadro FX540 128MB graphics
- 10,000 rpm HDD
- everything connected to a 940 vA APC backup battery
I ran this system for many months, maybe a year before this high-pitched sound started happening. It was probably just a little over a year ago when it started happening, but I just never got around to troubleshooting the cause. Has anyone experienced anything like this? I hear this high-pitched sound coming from the tower case all the time, which is annoying enough, but it's even more annoying when it's amplified by my home theater receiver.
*edit I should add that my APC backup says it's providing 194 watts of power right now, so the power supply is nowhere near capacity, yet it still makes this continuous high-pitched sound.
I wouldn't be surprised if the power supply is going bad. I've had power supplies make high pitched noises like that when they are in the process of going bad. I think the noise is caused by bad capacitors. I've never had the sound transmitted to my speakers before though, but a bad power supply is my best guess. If you have time then i would troubleshoot it by using one of your other power supplies. I suppose it's also possible that the two noises are not related.
Edit: you may also want to check the caps on your motherboard an make sure none of them are bulging or leaking, I think they can be noisy too but I've never had it happen to me.
I have the same issue with high-pitched noise coming from my PSU. It's a cheap model from a cheap vendor, so I'm not all that surprised. Bought the mid-tower along with PSU for 60$ or so. I'll buy something more serious (eg. Corsair) later on. Awesome that someone could pinpoint that bad capacitors is what's causing it.