Dirty video head! Playback newly opened blank tape for five minutes, after that eject, reinsert, playback then eject again five times, these will serve as your video head cleaner, never use "video head cleaning cassette tape" for it will only damage your camera. Most camera has built in video head cleaner installed inside and activates only when you insert, initial play/rec, and ejects a tape. If the problem is still there you need pro fix then.[:0)
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