Suzuki Omnichord OM-27

Here is my Omnichord, it works but has some interesting quirks, that may or not be faults, for me they add a unique sound to it.

All the keys and buttons work, but most of the time it plays a Chord note as well as the bass line, which can be used to great effect. The harmonics seem to warble (pretty sure this is analog).
I'll see what I can upload here as a video
Not sure if this has been modified or circuit bent, I think it's just age producing some unique effects 👍
Is the sustain extra long on this? Sometimes I think so

Usual crackles from the volume knob when turned

Not actually sure if the headphone socket works, I only have 3.5mm set

Has original but tatty box

No psu or batteries supplied