Siel Cruise Mono Section Fade Out

I have a problem with the mono section of a Siel cruise.
If anyone has experience with this problem, i’m very grateful for any advice.

It only gives a sound once, after the fade out it won’t make another sound, unless the register ist switched off and back on again. Most of the time it won’t make another sound after the first fade-out.
A big Thank You in advance :grinning: :monkey:

SIEL CRUISE

POLY SECTION WORKS

MONO SECTION FADES OUT AFTER 2 SEC. ALL REGISTERS EXCEPT “GUiTAR”

IF ANOTHER KEY IS PRESSED WHILE THE

SOUND IS PLAYING, IT PROLONGS THE

FADE OUT

HAROWARE LOOKS OK

NO CORROSION

FUSE REPLACED

ALL PLUGS DISCONNECTED AND RECONNECTED

GROUND CHECKED

ONE TIME THE SOUND TOOK 7 SEC. BEFORE FADING OUT BUT ONLY FOR ~ 5 MIN.