I don't know what Mac disk repair utility is, but if you have a removeable SD card, you could plug it into a PC and run "Error Checking" on the SD card. I don't think that's likely to solve your problem but it's probably worth a try.
As Funkylogik said, I'd:
1) Uninstall any recently loaded apps to see if that fixes it.
2) Run a complete Titanium Backup back-up. Do a factory reset (or a cache wipe if you're rooted) and then a complete Titanium Backup restore.