This same problem started on my LG BD570 intermittently about a month ago and progressively got worse. Would ff 3 mins, then 4 mins, then 3 mins, etc. On 6/23, I reported it to NF, they said they had never heard of it, had me reinitialize NF and a few other things. Finally told me it's a LG issue.
Spent an hour with LG support, updating firmware, reinitializing, etc. finally tech told me machine needed repairing. I didn't believe him. Since the firmware update now I fast forward in 6 min increments.
Found this website and called NF back. Asked tech if she was familiar with problem, she said no. Inquired why wast it then I was reading multiple posts online with people who have called NF to report this same issue and all of us are told that NF has not heard of it?? She persisted and so did I. I really persisted. Finally she spoke to a supervisor and came back and said this is a known problem, they are working on it.
The take away? Call NF and persist. Make sure that they get your model number so they know which devices are being affected. Make sure they know we want a fix ASAP. If you don't let them know how it is affecting your model, a fix may take longer or not come.