When I don't use my Amp for a few days, I sometimes have to flick the mute switch up and down a few times for the right channel to work properly. Now the right channel sound has gone permanently low, no matter how many times I flick the mute switch up and down. There is also an intermittent crackling sound that appears sometimes, but only when the amp has no input? Ive tried DeOxiting the Mute switch and even used a hypodermic needle to try and get the DeOxit into the right spot.(without success, by the looks) Does anyone happen to know if there is by chance an easy way of cleaning this mute switch, other than taking the faceplate off to de-solder the switch, then take it apart and clean it? Im guessing there isn't an easy way but I know theres some geniuses lurking around AK, so I thought I should at least ask first before diving in head first. LOL Im thinking the crackling sound might be a separate issue, like a leaky transistor? but Ive replaced all the transistors with modern equivalents about 4 years ago, all except for TR11,2sc735. TR13,2sa562. on both sides of the driver board? Any ideas, suggestions welcome.