Dirty or worn out heads is the usual symptom. The heads are very fragile so be careful cleaning them. An experienced tech should be able to tell, at the time of cleaning, if the heads are beyond their Use-by-date. It's interesting to see in for sale ads that video only has dirty heads. 99% of time they are worn out-beware.
Peter
April 2007
if your getting snow on the screen buy some de-icer
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Try fixfault.com to fix cassette recorders.