I have a old school kustom head from the mid 70s. Solid State (no tubes ) Sometimes and I think its weather dependent the thing sounds nice and warm like its suppose to. Other times (90% of the time) it sounds extremely distored and the lower the tone the greater the distortion. Any Ideas? The distortation is reguardless of the source and I know its the head not the cab because I ran the cab into another amp and it plays fine and I ran the head into another cab it it sounded like trash.