Originally Posted by Simon - PG Music
You might also run into issues as the microphone input provides power for the microphone (I believe around 1.5v). This isn't likely to damage anything you plug into it as there are likely current limits, however it may adversely affect the sound quality (adding a DC offset which could cause asymmetrical distortion). You can get around it by adding a capacitor in series to block the DC, but that can also adversely affect sound quality (it would act as a high pass filter and would affect phase).
If correct, that's a bit surprising.
All the signals on the jack must be single-ended, so any DC would affect the performance of a dynamic mic or headphone by applying a bias to the coil. It would certainly have to be current-limited to perhaps microamps, if only because the impedance of the circuit needs to remain high enough to get a sensible signal. Could headset mics normally be electret? Maybe.

Jazz relative beginner, starting at a much older age than was helpful.
AVL:MXE Linux; Windows 11
BIAB2025 Audiophile, a bunch of other software.
Kawai MP6, Ui24R, Focusrite Saffire Pro40 and Scarletts
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