I had about 2000 tandems 3000 jumps 8 years when I got burned out. It was caused by several things. I quit skydiving for 2 years and was even more unhappy. I'm back now and banged out 1000 in six months. All it took me me was to move to a different drop zone. I should have done that from the beginning. I think that is way a lot of instructors move so much, it keeps things new and exciting.
Blue Skies