Crackling through my speakers

Hi all, whilst playing a bit of music last night, a steady low-ish volume crackle started through both speakers. I powered off, waited a bit, and powered back on. The crackle came straight back.

I replaced all the valves, the crackle was still there. So, I'm stumped. Has anyone got any ideas, please?

 

Sounds very much like a bad joint somewhere in the stereo chain - I'd start by gently moving volume control knobs and the like. Do it methodically through the entire signal chain. Once you've eliminated all the 'moving' bits, start on the interconnects/speaker leads etc. When I've had this in the past and it has affected both channels, it has mostly turned out to be knackered control pots of one sort or the other! The important thing is be methodical - once you've eliminated everything you can get to, it must be something you can't, so start changing/removing boxes. Hope this helps.

 

Cheers, I'll give that a go.