I've run into a similar issue that's already been posted here, but, it seems as though the solution did not work on my end. I know there's something rudimentary I'm overlooking, but I just can't seem to find it.
Basically, soloing one track, will solo all tracks.
I'm running Logic Pro X 10.5.1.
I've checked to make sure the tracks weren't grouped in any way, and have also checked to make sure the channel strip and number were unique for each track.
Here is a link to download the project itself if anyone wants to take a crack at it. I've also tried restarting logic and my computer. It only seems to happening in this one project; all others are functioning normally:http://www.mediafire.com/file/9r4qdstwf ... x.zip/file
Any suggestions/advice are greatly appreciated!