emusonacid! legacy

My E4K's MIDI functions are set as follows:

Channel: 5
Mode: Poly
ID: 0
Local: Off (it's also used as a MIDI controller so it's connected to itself)

When I switch it on, it defaults to MIDI Omni On, i.e. its sound is played by my other controller whatever channel the latter is set to. If I enter the Master --> MIDI --> Mode menu, the display shows the correct settings and when I exit again, everything is back to normal!

The same thing happens if I enter Preset Edit mode. I have to go to the MIDI menu and exit again.

The E4K runs under EOS v3.00b

Have I done something wrong?

Gilles