1.piezo pickup is loose
2.piezo pickup is faulty
I have done repair on yamaha kick pad
Will do for you free of charge.
Come over on Sunday at 12 pm to bedok north blk 524
SMS 96927646(Alias)
It could also be your trigger or cross talk settings. If these are set to higher levels, sometimes one hit on another pad could cancel the sound on your bass drum. This is particularly true of e-kits that have a lower polyphony limit.