Here's what I want to do, and what I have been doing.

I set up track 1 with Cakewalk TTS-1 as the synth plug in. I will only describe the 2 MIDI channels I want to discuss for brevity.

I have a piano set on MIDI channel 9, assigned to the 9th slot of the TTS-1 mixer screen.
I have strings set on channel 2, assigned to the 2nd slot of the TTS-1 mixer screen.

How can I play those 2 sounds stacked together?

I can't figure out a way to make one controller play 2 MIDI channels at once, since the controller can only send MIDI data on the selected channel.

Can I somehow set up another instance of that TTS-1 synth on another track and put the piano and strings on the same MIDI channel by putting them onto 2 different places on the MIDI mixer screen? I want to do this to play both layered sounds when I play on the controller, not just clone the first take onto another track.

At MIDI wits ends here.....

I am using the new 1040XTRAEZ form this year. It has just 2 lines.

1. How much did you make in 2023?
2. Send it to us.