Hum with Bottlehead Crack

[hpleung]

Hi,

I plugged in my bottlehead crack since the last time (a few months ago) and notice a Hum. With RCA plugged in, but no music playing, Hum does not exists at 0 volume but as you increase the volume, the Hum increases.  With RCA disconnected, I hear a different noise. More like a buzz.

When music are playing, it sounds great and you cannot notice the Hum or noise.

Any ideas appreciated.

Thanks.

 

[Tom-s]

The fact that your volume pot influences the hum'; moves the source of the hum ahead of the volume control.

I may very well be not Crack related. As there's no hum with volume 0.