Diezel D-Moll volume changes and loud crackling

[13_strigoi]

My D-Moll recently started with loud crackling and volume changes. Is this likely a preamp tube issue? Thanks.

[Edit] Nevermind answered my own question pre tubes it was.

 

[Peter Diezel]

Please turn down the master und listen
if the crackling dissappears.

If yes turn down the channel volumes.

If yes, turn down the gain pots.

Best,
Peter