So I recently bought the J Mascis Jazmmaster Squire and love it for the most part, but noticed that sometimes when I switch from pick up to pick up that sometimes the pick up will be off, basically. For instance, I'll be playing on neck, switch to bridge, and all of the sudden no noise. Then I only am able to fix it by going to a different pickup and re-selecting the pickup and that usually works. It's not a big deal but definitely scared me the first time and it is still pretty annoying. I don't know anything about repairs, and am pretty hesitant to mess with it in fear of messing something up (not to mention that I wouldn't even know what I'm trying to do anyway). If it is a really easy fix though I'd consider it. I am also willing to spend money if needed to go see a professional but I'd like to know what you guys think I should do first.
Sounds to me like the switch is either dirty or faulty.. if it's brand new.. bring it to the store you got it from.. if it's used with no warranty, spray little bit of contact cleaner by the switch and move the switch from bridge to neck pickup 3 to 4 times.. make sure to wipe off excess fluid (the purpose of switching bridge to neck pickup is the movement loosens any gunk or dirt inside that affects contact)
I would say that the switch needs cleaning. The first thing I would try is a dose of contact cleaner, which you can buy from electronics supplier. You might be able to do it just by squirting some into the top of the switch and flicking across the pickups a few times. If it is a blade type such as Gibson use, take out some of the pickguard screws so that you can lift the pickguard enough to see the switch, and squirt some in from the side. I had to do this recently on one I was working on.
Could be dust, or it could be that some of the wiring in their isn't soldered on to well, but if it should ever get worse. It wont be a big deal because it would be pretty easy to fix.