standby switch, whats up with the snap, crackle, pop?

I have seen several reasons for this... the main ones are:
Bad ground, or a ground that is faulty or not having a very good connection, really
check around the filter caps.
Bad filter cap, this is kind of rare (not the bad cap, the bad cap making that sound)
Bad power switch (I see this a lot more than I would like to... geez, is a good switch that much more?)
Bad wiring to the first cap... check all of those solder joints!
Arcing somewhere from inrush current... I have sometimes seen these elusive
"wire was slightly crimped/cut/whatever here, and now it starts to pop when cut on"

Most of the time I find the problem is a ground, or the switch.

Hope that helps some.

 

Have your amp tech (or if you DIY) add a .02 @ 600 V cap across the switch terminals. It makes a nice suppressor for sparks and arcs that make noise and kill switches prematurely.

Many, if not all, of these standby switches are rated for a lower voltage and a higher current (old Fender's are really bad culprits for switch under-rating) and the caps make them survive the arc better when used at DC. I guess the Engineer's figured higher voltage and lower current would be okay...

 

Just got a traynor yba-1 back from a recap retube, and its doing this also. Its freaking me out! I am about to go on tour for 3 weeks, so I dont have time to drop it back off to have him check it out. It wont cause any damage to speakers or the amp?

 

Thanks! Used it on a gig last night, and there actually was no snap crackle or pop.