I have a very annoying issue and I'm looking for someone to help me. I can hear a very high frequency coming from my speakers from time to time. I tried very hard to troubleshoot it but I can't. Here's what I've found out:
1. I'm sure it comes from the speaker because the noise disappears the instant I switch the power of my speakers off.
2. The high frequency noise has constant pitch, but alternatives between on and off randomly, like someone is playing with a switch.
3. Using the same soundcard, I connected my earphones to it and there is no such probem. The audio is crystal clear with my earphones. So I'd bet it isn't the sound card.
4. I tried switching all other electronic appliances off in my room to eliminate inteference, then play music to the speaker using my phone - the problem still exists, though not as noticable.
So the question is, is this because my speaker is cheap (U.S. $100 equipvalent), or because of my 3.5 mm to RCA cable? I tried switching another cable (also 3.5 mm to RCA), the high frequency sound is still there randomly and it's super annoying. Will RCA to RCA cables solve this problem? My sound card only outputs 3.5mm, if it's cable problem then that means I have to upgrade my sound card as well.
Anyone has a similar issue?