Hitachi C29-F200 29" TV "audio turn agc" Questions

audio is scratcy and low no matter how high i turn up the volume.i tried tuning it to solve the problem but every channel has the same audio result.noisy and scratchy.i have lost my service manual for

turn the volume right up, i hear faint soiunds but i cant make out if its static/audio circuit picking up random interference. Thinking it is relating to the AGC but need help as this is effecting av,

...turn the power off with the remote it goes into the next servicemenu item and the tv has to be turned off manually. PANASONIC: Panasonic TV's after 1996 can be set to "Serviceman Mode" with the ...