Feeds Locks up during import.

Hello,

I am using the feeds importer and while uploading a .csv my feeds has locked up at 54%. I've used this importer many other times with no errors. I can't see to get it to release. Flushed all cache, new browser window, rebooted my machine. Any account I log in with still gives me a gray box with the text Importing (54%)

Any idea's?