DO NOT use a swab to clean the heads of your camcorder EVER! The heads are incredibly delicate and brittle and you can snap one off quite easily. Personally, I use a dry-type head cleaning cassette, but I don't need to use it very often at all. They are somewhat abrasive, so don't overdo it.
My Canon XL1s started to get sound dropouts only during the 1 year warrantee and they said run the dry cleaning tape through for 11 seconds. It worked. But I had to do it about every 4-8 hrs of tape. I was using only JVC tape.
JJK
I use only the recommended dry type cleaning tape.
Does your camera / deck show head hours?
You should follow the manufacturer's directions on how often to have
the heads cleaned and when to send in for tape path cleaning and lube.
It's just that I've had loads of cleaning prompts from cameras over the years and usually the cleaning tape works... sort of... for a while... and then I seem to get problems/drop outs/ rejected tapes again. It just strikes to me that the head now and again needs a proper clean with some solvent and not just the tape. Always used to clean VHS heads with meths and a swab and it worked great!
If you aren't scared to do it, it isn't that hard to clean the heads manually.
Get some cleaning swabs and isopropyl alcohol (91% type). Dip the swab into the solution and gently reach in to the shiny video head through the tape door then move the Q-tip forward and backwards (in the direction of the thin lines). Be careful not to push any component in the process, including the video head.
For a much better description of what to do than I can muster up, fellow Vegas user John Beale has a wonderful description of how to clean the head, capstan, pinch roller. etc on his incredible website.