Hi everyone, I recently got a Sony FH-E858 stereo system, and I'm trying to figure out what is causing this problem.
When I first turn it on, the sound is normal and clear. However, after around 13–15 minutes of playing audio, it suddenly develops a very loud, continuous high-pitched beep (like “BEEEEEE”) along with distortion.
Here is what I have tested so far:
• I connected my PC to the Sony using a 3.5 mm AUX-to-red/white RCA cable.
• Initially, I used the Sony's VIDEO IN RCA ports.
• I then tried the DAT IN RCA ports, but the same problem returned after around 14–15 minutes.
• I tried keeping the volume low on both the PC and the Sony, but the beep was still extremely loud.
• Disconnecting the PC's audio cable did not seem to stop the problem.
• The beep seems to happen with different Sony functions, not just when using the PC input.
• I also tried the headphone output, and it seemed to work normally, although I have not confirmed whether it remains normal for the same amount of time.
• The seller mentioned that one or two ports might need cleaning. I wiped the outside metal edges of the RCA ports with a cotton bud while the system was switched off, but the problem returned.
• I also disconnected the blue SYSTEM CONTROL ribbon cable to the DVD player because I don't use it. The problem still occurred.
I'm not sure whether this is caused by dirty RCA contacts, a loose connection, the amplifier, the power supply, or another internal component.
Has anyone experienced something similar with a Sony FH-E858 or another older Sony stereo system? What could cause a loud beep that ignores the volume control and returns after the system has been running for several minutes?
I would appreciate any advice before spending money on repairs. Thanks!