THA-REAPER wroteI'm using 3.5 it seems like the button is just gone. I only have the one on the transport bar for master fader. Is there something I may have turned off?

https://i.imgur.com/L1cYMse.png

The mono/stereo channel buttons you are referring to are only present on audio tracks. If you want to switch between mono and stereo on instruments tracks, use the Binaural Pan plugin and use the mono button on that.

Ah.. Thx for that tip.. I usually send a stereo Instrument track to a new buss and then hit the mono button on that buss

Your way = smarter

brettgoodkin wroteAh.. Thx for that tip.. I usually send a stereo Instrument track to a new buss and then hit the mono button on that buss

Your way = smarter

No problem.

I have this exact problem too but it's on an audio track.
I remember using it earlier on this same project.
Now the mono/stereo button is just gone!

How do I get it back?

Things I have already tried:
-Use a plugin that says mono to stereo (no dice, signal is still mono)
-

Help!

Hi and welcome to this forum

Mono/Stereo buttons (or 'channel mode' as it is called) for audio channels can be found in the track column left of the arrange view. You may have to increase the track height to see them.

Buses have their channel mode button in the console.