This must be a bug!
I would expect repeatedly pressing the TAP button to change the tempo of the arpeggiator or sequencer. Surely, this is the main/only purpose of the TAP button.
However, when the arpeggiator is running, all the TAP button does is to mute notes for as long as it is pressed in. Who needs a MUTE button?
And when any sequence is playing any preset (i.e. green PLAY button and white TAP button are flashing at different rates), pressing the TAP button either:
(a) increases the sequence length (randomly?), or
(b) deletes steps that are playing at that time.
I can reproduce this effect every time, but I cannot change the tempo by tapping the TAP button.
I am using the latest firmware revision (1.1.0.73).
This issue is referred to by other MatrixBrute users, for example:
Pressing tap tempo when the sequencer is running erases sequence data!
What's up with that?
Will this serious bug be fixed by the next firmware revision? When is it due?