I check the user manual and it says that turn the knob which controls the delay time to the maximum.
The milesecond will  become note.  But that's the problem. I CAN NOT turn the delay time to the maximum even I turn the knob to the far right.

What can I do now?

bty, I have already updated to v.2.04 and also try resetting the m9 many times ,still doesn't work .

Can anyone teach me how to solve this?