I have a 2003 VW Beetle Conv. Recently the driver side window does not want to go back up once I put it down. About half way it makes a grinding sound. It will go back up about half way from being all the way down but that is about it. I can close the door and it will go back up with a little assistance. I know these cars have issues with the cables. I guess my question is does it sound like the cable is about to go or does it sound like a regulator issue?