Default Audio Transition no longer being applied.

Hi there. 

All of a sudden, my default audio transition is no longer being applied. This is with both the shortcut and the menu item in the sequence menu. For context this is a long clip chopped up and I am attempting to crossfade between cuts. So its not two different clips at their end points. I can still add the default video transition, but not the audio one. 

No doubt it is my fault and I've pressed something I shouldn't have pressed, as I haven't updated the app yet, still running 24.2.1. We keep a policy to not update to the latest version for stability reasons. Ironic huh? 

Thanks

Billy