Front Seat Belt Retractor problems of the 2004 Nissan Titan

Seat belts locking up. Seat belts on front passenger and rear outside passengers have a retract system that does not allow passenger to lean forward. Belts are locking up requiring passengers to disconnect belts from belt latch and letting belt retract all the way back to stored position. Then they can be pulled out and reattached and they work for awhile. They will do this at anytime. There is no set time that it happens. It happens with different passengers but mostly with women. The drivers seat belt does not have any lockups. The seat belts have been replaced 4 (four) times to date and are going to be replaced again as soon as they are received by dealer. They have been covered by warranty. We have lost count of how many time this has happened. Probably 500+. The safety issue is that belts are disconnected while driving and then reconnected leaving the passengers unprotected during this procedure. Belts just get tighter and tighter until they have to be released and reset.