Musescore 3.x midi out ports

Hi all,

Having an issue with Musescore 3 and multiple midi out JACK ports to an external Linuxsampler instance, namely that anything after port 2, channel 1 is ignored and notes don't get sent on the "staff channel" changes. So I'm not sure how I can work with several ports of 16 channels each in Musescore.

The midi channel select feature (i.e staff text properties and select between arco/pizz/tremolo) seems to not work for any additional channels if port 2 or greater is selected. If I select port 2, channel 1 for an instrument, the arco plays, but staff text for switching to port 2, channel 2 or 3 for pizz and tremolo is completely ignored and Linuxsampler stays silent. Yet, I can switch to Port 2, Channel 2 in the mixer itself, and I hear a pizzicato sound, though this is still technically just the first channel it is selected as.

Is this a bug? Are there any known workarounds?

Thanks,

Andrew.