i have too noticed this on occasions, alot of times, the phone screen doesnt come on when a phone call arrives and the phone just vibrates/rings, then eventually it comes on but its too late =/
i have found that not using a live wallpaper greatly decreases lag in the phone
hopefully this stuff could be fixed in a future update =D
this has happened to me before. very frustrating :angry: but it hasn't happened for awhile, especially since i overclocked. *fingers crossed*