As the title describes, sometimes, but not too rarely, when I have an incoming call I cannot fully slide the lock to answer. It will get to like 20-30% and then jump at the start. Sometimes after many tries ill make it while other times i just lose the call. There seem to be lots of people with this issue but couldnt find an answer.
Problem happens on IPhone 4 with latest software running. This occurs with calls coming from contacts but 99% of incoming calls are from contacts anyway.
Best Answer
Almost a month after doing the reset, the issue has not appeared, so I believe this has been solved. Dirt on the screen did not apply on my case but I guess it can cause this issue in some cases.