Chord notes not played simultaneously while in note entering mode using a MIDI keyboard (Linux Mint)

Hello everyone,

I have connected a MIDI keyboard to my laptop running Linux Mint via USB.

So far, everything seems to work as expected. When I hit multiple keys at once while in non-edit mode (in order to play a chord), the corresponding sounds are played simultaneously.

Now I would like to enter music notes to my partiture using the keyboard. But unfortunately, as soon as I switch to note entering mode, I can't play multiple notes at once any more.

If a chord is played, the notes are also being entered as a chord to the partiture, however their sounds are not being played at once anymore, but as they were single notes that are hit in very short intervals.

For me personally, this wouldn't be such a big deal, but the setup is intended for my grandfather who has been playing classical piano for decades and this strange behaviour of notes being played after each other instead of a chord in note entering mode is therefore very irritating for him.

I would like to digitalize his old compositions with him using this MIDI setup, since he has no access to his piano room anymore due to a recent stroke.

Hope someone can help us.

Many thanks in advance for your support!

Kind regards,
Christian