Sorry, I meant to post this in the X1 forum, not instruments. Thanks to all for you replies.
I tried resetting my audio engine, but that doesn't work. I seems like the only way is to go to preferences, and click "OK" -- I don't even need to change anything in preferences. Btw, when I hit "P" to go to preferences, it takes about 20 seconds for the preferences screen to appear.
I'm using ASIO4ALL and the USB out on my computer. The problem started when I got a new laptop about a month ago. I didn't have the problem on my previous laptop.