The fuse keeps burning out on for the brake lights?

The fuse keeps burning out on for the brake lights. I have had the wiring checked in the back where the lights are to see if it is lose I have replaced the fuser several (lots) of times. The parking lights, headlights and back light or signal lights are not going out just the brake lights, although once in awhile the signal light to the right will go out and then come back on but this does not happen all the time when the fuse goes out. The signal light sometimes working and sometimes not working started first before anything else then with the bulb burning out in the back on the passenger side (right side) and that was replaced and then I started having to replace the fuse first every 3 or 4 day and now it is all the time. I put in a new fuse and then take off and shortly after that it is out again and only the brake lights go out and the signal to turn right will sometimes work and not work.