Monotron Delay - wrong cable into headphone jack

[gas24]

Firstime user here, both of the forum and the Monotron Delay. I was playing arouond with it today and trying to connect it with my Monotribe.

After trying a few configurations with a aux cable to get the two sounding together - Monotron aux to Monotribe audio in; Monotron aux to Monotribe syn out...AND from the Monotron Headphone output to the audio in on the Montribe. I wasn't getting anywhere and then looked at the manuals and the Monotron delay manual says:

"Do not connect a cable with a monaural plug to the headphone jack."

I fear I might have done just that. Did I "mess up" my monotron? What are the possible repercussions of connecting a cable with a monaural plug to the headphone jack? The manual just says not to do it.

I can't be sure, but both devices might be acting a little differently, sonically speaking.

Obviously I am a complete novice, when it comes to synthesizers specifically and electronics more generally. Maybe I should have just stuck to my acoustic blues playing....

Any help or insight would be much appreciated.

[LM]

When you connect a mono plug into a stereo jack (even if dual-mono, like the Monotron) you are actually shorting the right channel to ground. It's not that it will instantly damage the instrument, but it will interfere with proper functionality when connected that way.
On the Volcas (for example), it messes up with the analog sync when you do that to the audio out.

[synthpeter]

The schematics of the Monotron Delay (which you can download from the Korg website) show that there is a series capacitor and resistor between the output opamp and the headphone jack. So, inserting a mono cable will not damage the Monotron, but the way the headphone jack is wired will connect the cable tip to sleeve, leading to no audio output.