N64 carts randomly resetting

So we've got a PAL Majora's Mask cart here which for what ever reason just keeps randomly resetting on us. We're pretty confident the problem is the cartridge, we've played many, many games which don't exhibit this problem so we're ruling out the console, we've also played a bundle of expansion pack games and they all work fine as well, so we're ruling out the expansion pack as well. Anyone got any idea why its doing this and possibly how I can fix it? The cart is pretty much useless so all options are open really.

 

Thermal expansion of the cart and/or expansion pak? The game did push the N64 harder than any other title AFAIK. Except maybe Perfect Dark.

 

So you think it could be the expansion pack? I thought that originally but we tested it with a bunch of games, like DK64 and it worked fine with no resets at all. :/

 

Have you given the cart a thorough cleaning? My copy of Bad Fur Day did the same until I took a Q-Tip and some rubbing alcohol to the connector. I didn't think it was possible for games to get that dirty.