I have a HTC Sensation running Android 4.0.3 (HTC Sense 3.6, 3.33.401.53). Of late I've been having increasing problems with global lag, however this is really most noticeable on the dialler/phone app itself. By more noticeable, I mean several times worse compared to anything else.
I can open the contacts menu in the dialler without difficulty and filter by name to get the number I want up, however I get no response when I click the name (aside from a green flash of it to indicate I've pressed sucessfully). There's then a pause of I would say up to a minute in the worst cases before it actually dials. Usually I've pressed it multiple times in the hope of it working, whereupon it calls the person multiple times and I end up with several calls to the same person 'on hold'.
Is there any known cause for this or even better any likely way to fix it? I could do a factory reset if this doesn't get resolved as it makes the phone close to unusable.
The effect isn't really on answering calls, though there is a lag on that too (but not to anywhere near the degree).