Default [Q] G2 acting up on screen turn on

Hi everyone
I have been using sprint g2 for a little over a month with no trouble until one day when it started acting up. So whenever my screen wakes up, be it after the knock code or after receiving a call, it shows a phantom touch right in the middle of the screen. My screen wouldnt recognise any touch till that phantom touch is gone. In order to get that gone, ive to generate interference by multitapping randomly for sometime which seems to solve the problem. Interestingly my screen works just fine after the phantom touch is gone even for prologed usage..but once the screen turns off (by doubble tapping for instance) n i wake it up later, the problem reappears..ive tried factory reset n custom roms to no avail. Oh n one more thing, when i restart my phone n the first time it shows the unlock screen, there's no phantom touch but as soon as the next tap on pr a call ends,the prob reappears.
Guys ive been reading all threads n couldnt find a Similar issue solved...ur help would save me from hating this otherwise awesome phone...thanks indeed.