I just setup my MIM 50s Precision with 45-100 DA XLs. The relief is fairly low (0.012 to 0.015). The action is set medium low. I get no buzzing and it plays great. Except, when I slap it buzzes. I can pluck the string hard and I get no buzz. But slap it and there is a buzz. Also if I am playing on the E string and jump over to A, the slightest hit instead of pluck on the A string results in a nasty click / pop sound. I can play the same riff on another bass (50-105 EB flats, low action) and I do not have the same issue at all. Does this sound like micro tilt time? A while back the neck was set with more relief (around 0.020) and it slapped without issue. But I have never experienced a setup where it was fine for heavy handed finger style but would not slap and was so sensitive to my bad technique .