wondering if anyone else is having/had this issue...

since I've had the car (got it last winter), I've had to replace the passenger side rear taillight/turn signal bulb 3 times now (i get the hyper flash on the dash and when i check its the back bulb)...

no corrosion on the connection, all wires in tact, and the filaments on the bulb aren't even broke.. but when i change the bulb, all goes back to normal... and after a few months... i get the hyper flash again.. any ideas?