Signal flasher question

I have a '95 GMC Jimmy. For some reason, the blinker lights have always flashed REALLY slow. Is this a relay issue? What exactly makes then flash? I noticed the clicking comes from the dash behind the ashtray, and I think there are 2 silver relays in there- would changing those solve the problem?

I'm not too sure what the problem is... I think it may have something to do with a bad side marker light? When I first purchased mine, the flashers were REALLY slow, and lately its been going at a normal speed.. I can't link the two together because I'm not sure when it started going normal speed, but I know that they were always slow before I changed the bulb..

Yeah, maybe I'll just swap out bulbs and see what happens. The only thing is- it does it on both sides- so I'm questioning whether one bulb could affect all of them.

Problem found- it was a bad flasher unit (the silver cannister-like device under the dash). A simple $3 fix.