SNES/SFC Sound and Graphical Glitches
As with many cartridge based consoles, if you leave cartridges in them for too long whilst not in use you can damage the cartridge connector. If your SNES or Super Famicom has distorted or even missing sound and/or graphics then you may be able to fix it by simply adjusting the contacts of the cartridge connector.
Find a suitable flat bladed screwdriver. It needs to be the same width (or just under) of the contacts that you need to adjust. When you look closely at the contacts you'll actually see that each contact is in fact a pair of contacts, and each pair are in their own plastic guide, the screwdriver should be the width of the pair of contacts. Whilst holding the cartridge door open, gently push down on the top of each pair of contacts along one row, you'll see that the rest of the contact bends in a little, this is exactly what you want. Sorry about the quality of the photo, mmmonkey found it very difficult to take a good quality photo if the screwdriver pushing the contacts.
If after doing one row of contacts the console still doesn't work, then do the second row. Don't confuse the graphical glitches with the ones caused by running a 50hz game with an SFX chip at 60hz (as seen on here). Also make sure that you discharge your console before sticking a screwdriver into it, unplug it from the wall and then switch it on - you'll notice the power LED flashes briefly.
If it doesn't work, then it is possible to replace the cartridge connector, either from a another console with a different fault, or purchasing a new connector (eBay - probably an American seller). You'll need a Gamebit to take your console apart.
