No sound after adding drum rack???

[notinflight]

Hi,
So I'm new to Ableton. I have a project started and so far all it has is 2 MIDI tracks and an Audio Track.
I have some MIDI notes in the first MIDI track and Serum in the Audio track. MID 1 is routed to Serum in Audio 1.
It plays fine until I drop one of the drum racks into the 2nd MIDI track and then there's no sound from my
MIDI 1 Serum setup.
The only sound that will play comes from the sample player in the left hand menu where all of the instruments and effects are
or by clicking on one of the samples in the drum rack.

I deleted the drum rack track and there's still no sound from my initial MIDI or serum.

Does anyone have any idea why?

Any help appreciated!
Thanks!

[notinflight]

NM I guess Serum was no longer armed after adding the drum rack. Now the issue seems to be that I can only arm serum or the drum rack... not both … I feel like reaper was never this complicated

[pottering]

You select and arm 2 or more tracks using the same "ctrl/cmd" modifier you use to select multiple items in any other software.

It is years since I last used Reaper, but I doubt it uses another standard.

https://www.ableton.com/en/manual/recor ... ing-tracks