Yamaha DTXpress/DTXplorer/DTXtreme

Unfornately, I have looked for the option too, but it'is not possible. A
solution would be to have external click with an input where you plug the
headphone output so the click signal would not come into the brain(you would
plug your headphones in the click output). Another solution would be to
record your drum track as a midi track in the internal sequencer and then
replay the recorded track without the click(be carefull of the quanticize
option).
A lot of softwares have an internal click which can be usefull in this case.