I find that when just one lift stalls, and it stalls early on (which in your case it is early on since I'm assuming you are powerlifting), it's often due to weak links like from strength imbalances or poor technique. If you're following the true 5x5 program, guess what? You're neglecting so many muscle groups that support your strength development ...
You can rotate the rep ranges, which will help you recover better, but make sure set-up is good (some people vary the grips etc). Also, make sure you aren't neglecting muscle groups (e.g. all parts of the: delts/back/triceps etc...)
I find it ironic that those seeking strength will say 5x5 will build huge muscles/strength unlike those "stupid" bodybuilding routines...but nothing could be further from the truth with a decent modern bodybuilding routine where weak points are not made even weaker like you do with something over-simplistic like 5x5.
Good strength development is all about bringing up weak points, and you can't do that with just 5 exercises/week...most powerlifter do more than just that (assistant exercises)