Both pads work alone, but one note disappears when I hit them together

This symptom has a precise condition: each element responds correctly on its own, but one event goes missing when both are hit together. eDrumWork classifies it as D09, excessive suppression or cancellation.

The eDrumWork diagnostic records each pad on its own before asking for pairs. Otherwise, a pad that was already silent could be blamed on the simultaneous hit.

Prove it in two stages

For a snare-and-kick pair:

1. play several snare strokes alone;
2. play several kick strokes alone;
3. confirm that both notes are stable;
4. strike both together several times;
5. count pairs in which only one event arrives.

One badly played pair is not enough. The note has to go missing repeatedly, on an element that responded correctly on its own.

MIDI order is not gesture order

Nearly simultaneous messages can reach the browser in either order, so the pair is treated as an unordered group containing A and B. The first message is not assumed to belong to the first target.

The tolerance applies to the gap between the two events, not to perfect sync with a click.

Protection intended to stop one pad's vibration from triggering another can mistake a genuine simultaneous hit for crosstalk. Reducing it may recover the pair but bring back D07, so every retest must alternate A alone, B alone and A+B.

If both Note On events are there but one sound disappears, look at plugin polyphony or the audio side; D09 requires a MIDI event to be missing.

Test simultaneous hits on my kit