Why ami experiencing a distortion noise while using av sony 21 inch ctv ha21m80

If there is distortion and noise, while using the TV, for on-air transmission, and there is no distortion or noise while using it AV, be sure that it tuner is faulty. Check the Ariel connection first, for discontinuity or loose contacts. If it found OK, replace the tuner. If you wish to get some details; check the site linked here. Viewing it in "Mosaic" or "Magazine" will make surf easy. Pull up older posts. Surf the site with patience. Do a search by type in the brand name of your device at its search box and press "Enter".
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