Momentary pain when ascending on squat/deadlift

[rob112]

I've had this on and off since around last June, sometimes it doesn't effect me at all, and sometimes it does. I first thought it was hamstring, then groin, and now glute. It is hard to tell. It litterally happens very fast and only when I start an ascent. Just curious if anyone here has had this or if they have a chance of pinpointing the area so I can try to strengthen it. Oh, and why I can't tell is because it is kind of the area where they all tie in.

Thanks in advance.

Edit: also, never once happened in deficit deads, just regular conventional.