Tracks occasionally overwriting below tracks

[TheMennoKnight]

Using Premiere CC 13.1.4 on Mac Mojave 10.14.6

This only happens once every few weeks, so I don't know how to replicate the issue- curious if this has happened to other users though. I'll be in the midst of editing when I notice that an entire audio or video track was, at some point, shifted one track down, overwriting the track below it. Sometimes video and audio will do this at the same time. It creates all sorts of problems and can take up to an hour to fix. 

Anyone know why this might be happening? I edit animatics so I'm usually working with jpegs and movs. I'll sometimes lasso a selection of clips and use alt+down to shift them down a track, which is the only thing I can think of that might lead to this problem- but I'm only lassoing a few clips, not the whole track. 

[Steve Griffiths]

I've not ever seen that issue in PP 2019 on Mac. Trying to think if there's any action you may be making that accidentally causes this ... ?

When moving clips into another track I tend to 'option lasso' on Mac to avoid picking up any audio tracks associated with a video clip ... so they don't move. Other than that nothing comes to mind.

Could you try (for a while) keeping your tracks visible whenever you move a clip just to see if you can see this happening and perhaps find out why. 

[TheMennoKnight · Accepted solution]

Update: I finally figured out what was causing this. I don't know why Premiere has this functionality, but if you select a cut and press alt + down arrow key, all the clips on targeted tracks will overwrite the track below. I must have accidentally done this when trying to trim using alt + left/right arrow keys.