Toshiba Regza 32C3000A tv sound keeps droping out, the mute button when pressed on and then off brings it back on. seems as if the tv is auto muting itself?

Is the arrow through the speaker icon when its not in mute?

When changing the Settings on your detector, please keep in mind: Each time the unit is turned On the factory settings of Highway and Auto Mute-On will be set. They can be changed while the unit is in use as described in the following sections.
Assistance Muting An Alert
Your detector allows you to quickly turn Off an audio Alert by momentarily pressing the Mute button. If you press the Mute button a second time during the Alert, the audio Alert will be turned back On.
Auto Mute Mode Auto Mute will automatically reduce the audio volume of all alerts after four (4) seconds for as long as the signal is detected. The factory setting for Auto Mute is On.
Highway/City Mode Setting your detector to City mode delays all X band audio alerts at lower signal strength levels. (A single beep will sound when the signal is first Notice detected.) This will reduce false alerts while you are driving in, or near, urban areas where there are many sources for conflicting X band signals such as microwave towers and automatic door openers. To change settings, follow the procedure listed below, which indicates what you will see and hear as you complete each step. The factory setting is Highway mode.
Highway Mode City Mode
Mute Button Press and release
To Turn Auto Mute Off X Ka L S
City Button Press and release
Press and release the Mute button while no alert is occurring.

Check your remote control for its infrared emission. If the remote does work for half mute, an other press must make the TV to full mute, and an other press the TV should be unmuted. Check the remote with new batteries.

Try Mute button, onscreen audio set up to make sure it is not set to OFF.

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ENTERING TO SERVICE MODE
1) Press MUTE button twice
on Remote Control.
2) Press MUTE button
again to keep pressing.
3) While pressing the MUTE button,
press MENU button on TV set.

you mean with all tv channels too? there might be an attenuation setting somewhere that has to be de-activated. Check the manuals. hope this helps and pls come back for a feedback

1. ENTERING TO SERVICE MODE
MUTE
S
(Service mode display)
3) While pressing the MUTE button,
press MENU button on TV set.
2) Press MUTE button
again to keep pressing.
1) Press MUTE button twice
on Remote Control.
2. DISPLAYING THE ADJUSTMENT MENU
1) Press MENU button on TV.
Adjustment mode
Press
Press
Service mode
Item
S Data
3. KEY FUNCTION IN THE SERVICE MODE
The following key entry during display of adjustment menu provides special functions.
Screen adjustment mode ON/OFF: TV (ANT)/VIDEO button (on TV)
Selection of the adjustment items : Channel s/t (on TV or Remote)
Change of the data value : Volume s/t (on TV or Remote)
Adjustment menu mode ON/OFF : MENU button (on TV)
Initialization of the memory (QA02) : RECALL+Channel button on TV (s)
Initialization of the self diagnostic data: RECALL+Channel button on TV (t)
“RCUT” selection : 1 button
“GCUT” selection : 2 button
“BCUT” selection : 3 button
“SCNT” selection : 4 button
“SCOL” selection : 5 button
“TNTC” selection : 6 button
Convergence adj : 7 button
Self diagnostic display : 9 button

Replace the convergence IC and check power resistor for leakage, if values are not exact replace them. Once the parts are in place perform the alignment.

Thank you & post back again if you need additional info.

I know one code please try if it helps 1 press mute button once on remote control handset. 2 once again press &HOLD remote hand set mute button. 3 while keeping mute button pressed press menu button on tv set. good luck

WHen I hit the mute button again to bring up the volumn the sound remains muted. I have tried all other channels, direct cable and even a dvd player connected. No sound. I unplugged all the boxes and tv and then plugged in again in a attempt to reset what might be wrong. Still no sound. solution 1 while operation mute button has got demaged or pressed more. 2 sound section might have gone defective in tv 3 no supply to sound section 4 or speaker defective or ic got demaged.