It's a fairly common occurrence for people on custom builds. I've noticed it when trying to do too many things at once.
There also apparently appears to be a link between SwiftKey and this problem from what I've read, or maybe that's an entirely different problem.
Mine have stopped after I disabled Google Services Sound Search.
A few things I've noticed are:
1)Random reboots/Phone overheating
2)Sluggish/unresponsive phone performance coming out of 'sleep' using double tap
3)Speaker/headphone Viper4 mod not working properly
Is a factory reset something I should consider if I didn't root the device until after the 4.4.2 update or is there something else causing these issues? I'm sure there is some user error in #3 as I'm going through the learning curve, but the most concerning is by far the #1 and 2, as I rooted it for the main purpose of increasing performance speed.