Major Keyboard Lag
Over the past few days I have noticed that I am experiencing a bad "lag" when typing in Pages. I can start typing, finish a sentence, and sit back and watch the characters continue to appear one at a time (about one a second) until the sentence I typed is finally finished. I can go on like that for more than a sentence, it is just getting difficult to catch typos and to know what I have written when words can take be 5-10 seconds to appear.
I am using Pages 5.5.3 (2152) and have not, to the best of my knowledge, updated it recently (i.e. it has been working without the lag in this version). I have no keyboard lag in Safari or Mail. There may be lag in other applications but I have yet to encounter it, and have not experimented enough to be sure.
I have rebooted the computer several times and it has also been shut down for at least several hours once since noticing the issue.
I am running 10.10.4 for the operating system.