Hi there people! Long time no see...
 
I've being using Reaper for a few years now, stoped with sonar when all the mess with Roland hapened years ago (the Vs-700 scandal), but I keep on updating my Sonar... I am on platinum now... Today I decided to give it a try again and got stuck with a, probably, stupid problem, but I am not been able to solve it by myself...
 
I have two soft instruments inserted in a project I am starting... One is a drum machine (Nythonat) and other a synth (Chromaphone)... I got nithonat running using the step sequencer... pretty sweet as usual... but when I click on Chromaphone's track to start recording it, it starts to receive the midi message from the drum machine step sequencer... What I am missing here??? 
 
Thanks a lot.
 
Peace.

Be sure you have the output of your MIDI going only to the proper input of each synths. Also be sure the synths are not outputting MIDI on their own. 

Change input on the Chromaphone track to the appropriate MIDI input instead of using the default All Inputs > MIDI Omni
 
Chances are Nythonat has "Enable MIDI Output" selected (the default for plug-ins which have the capability). This can be disabled when inserting the synth or changed in the synth rack by right-click the synth for the context menu.
 
 

Also, if Nithonat can echo or generate MIDI, right-click it in the synth rack, and disable MIDI Output.
 
Additionally, be sure the Input of each the MIDI/Instrument track is set to the specific port and channel that your controller will send on rather than 'All Inputs - Omni'. If you have 'Always Echo Current MIDI Track' enabled in preferences (the default), then the input of a new track will automatically switch from None to 'All' the first time it gets focus.

More than missing using Sonar, I missed this brotherhood vibe of this forum... Thanks folks!

brundlefly
If you have 'Always Echo Current MIDI Track' enabled in preferences (the default), then the input of a new track will automatically switch from None to 'All' the first time it gets focus.

I was going to circle back and add something about this too but could just delete my post entirely.

ProMusic27
More than missing using Sonar, I missed this brotherhood vibe of this forum... Thanks folks!

Its good to have you back.