All tracks play at once when I just want one solo

when making a recording, all tracks play simultaneously. I can not mute one and have other solo.
I presume I have turned something on in error but I want to switch it off !

In the little box to the left of the waveform there are “mute” and “solo” buttons.

If you have a stereo track and you want to listen to just one channel, click the 3 little dot’s and chose Split Stereo Track from the drop-down menu.

Thanks I used to use the solo/ mute button but recently all tracks are either on or off -it is not a matter of individual channels. I am building a recording with 3 plus tracks.
ANy other ideas welcome?

I found I need to press shift whilst applying the “mute” and “solo” buttons. Thanks for looking and hope it helps someone else to know this!

Edit > Preferences > Tracks > Track Behavior