ALSO,I tryed to post a link to a vcr head cleaning diagram link on the web,but it would'nt let me. Just do a google search and type in 'vcr head cleaning diagram',you'll find a couple very good websites that go into detail in this procedure.A video camera that uses tape as recording media is indentical in function to a vcr,just on a smaller scale.

Yes,no sound,possibly due to being dirty,but it would'nt be the big round shiny aluminum video head/drum.It would be the audio/control head.It would be located to the lower right of the video head/drum.Its oblong/rectangular in shape,with a chrome finish on the front.You can clean this one without worrying too much about damaging it,as there are no protrusions that your head cleaners would get snagged on,like on the video head/drum. Theres also a black erase head to the lower left of the video head that should be cleaned while your at it with the other two. Hope this helps you and good luck with your unit.K.Parks