Korg DDD1 help please - weird output

[frank01]

Hi, I just bought a Korg DDD1 drum machine that I'd like to possibly bend. Just to mention from the start, I have the settings on the drum machine correct and it should work as intended.

Currently only 1 sound will play at a time. If 2 or more drum pads are hit at exactly the same time no drum sound is heard except a short blip/clip sound. Even when recording a pattern, any drum pad that is hit at the same time that metronome is heard, no drum sound is produced. I should also mention that the drum sounds themselves do not play to completion half of the time i.e. very inconsistent and get cutoff mid-sound.

I don't see anything obviously wrong internally. What component could be responsible for this behaviour? Is it simply a bad volume slider? I thought this would be the best place to ask for help.  Thanks in advance to anyone who can shed light on this problem.
-Frank

[Circuitbenders]

Is there any evidence that someone has tried to bend it? I'd check out the solder side under the sound ROM's to make sure nobody has had a go at it and bridged some pins.

Does it work over midi?