[DW87]

Recently I noticed a ringing noise audible from the right cup of my headphones, almost like a high-pitched 56k modem sound if you can remember! It is connected to my pc but even with the cables disconnected and just the amplifier, I get this constant noise - I had it one time a week or two ago, and I switched it off for a while and came back and switched it on again and its been fine since, but now its pretty much constant, it kicks in instantly to a few minutes later of powering on. Once its there theres no getting rid of it. Does anyone know what this could mean?

 

[DW87]

I just tapped my finger next to the headphone jack and it immediately stopped, not for long I bet though! Connection problem here maybe?

 

[atbglenn]

More than likely a microphonic tube. Try lightly tapping on the tubes one at a time. See if it the ringing stops or changes. If so, change that tube...

 

[hughwi]

That sounds like microphonics from one of the tubes, could alternatively be a grounding issue?

 

[DW87]

Thanks for the replies - Its been fine since but I'll test the tubes if it happens again. Cheers