I have the same issue
I have the same issue using a Samsung Galaxy SII X.
I have taken the following actions to no avail:
- my screen protector does not conver the proximity sensor;
- the proximity sensor is clean;
- I have disabled proximity sensor (phone>call settings>turn on proximity sensor); and
- I have disabled automatic brightness (settings>display>brightness).
All of the above have been suggested within this and/or other forums. However, none of these solutions corrected this most annoying problem.
Some have suggested that the phone is the issue - however, suspect that there may be a software issue and that a patch or fix may be available would hate to have to exchange phones yet again.
Any and all suggestions would be most welcome.