Okay, it sounds like the problem is originating with the GL2 in the form of audio and video dropouts, etc. FYI, it’s not a good idea to change tape brands unless you get the camera seviced first. Some tapes are dry lubricated and some are wet lubed, so when you mix the two you’re inviting problems. I don’t see any way of fixing your present problem unless you want to try capturing your video to the computer using another camera/deck to see if it’s just an alignment problem with the GL2 or the tapes were indeed recorded with the dropouts. The only way to know for sure is to try the above method.
You should definitely get the GL2 in for service and tell the service person the problems you’re having with it. They’ll do a good cleaning and alignment for you. In future please stay with one tape brand. Both the Panny and the Sony Master series are good. You’ll be able to tell your boss that scrimping on tape quality is not the best way to impress his clients.
When you first put a new tape into your camera, fast forward to the end and rewind to the beginning. This accopmlishes 2 things: it pre-tentions the tape against the recording drum and also helps to throw out any microscopic bits of debris that sometimes get lodged in the tiny grooves of the heads. This practice will keep tape dropouts to a minimum.
Best of luck.
– Don