sound not stopping when all tracks are muted

hello people,

i recorded a sequence with six tracks, two of them internal programs on the mpc and four midi tracks using a korg m1 as external sound module.
i have soft through activated so i can hear the korg sound on a headphone attached to the mpc.
if i play or stop the sequence all is good, all sounds play, all sounds stop.
but if i mute tracks in track mute screen only the drum tracks mute properly, the midi tracks keep on playing with a weird sound not as loud as the normal sequence.
it says track mute on in the main window on all tracks but still the sounds are playing.
it is not the hanging note problem (which by the way occured once with the m1 while it was not in multi mode).
what can i do to mute this tracks properly?

thanks in advance,

peace jo

Take a look here

Maybe that will help you, if it's the same problem.

thank you stilo... that was the right hint and it solved my problem.

peace jo