Using the T7316E in an onair studio want to have external mute

Try pressing the mute (speaker symbol with diagnol line) or just press up/down volume button

There is a mute button on the phone. It is located under the volume control button.1st button of three to the left. It is also possible your handset to the phone has gone bad.

there may be problem in your amplifier or the mute signal or the input signal from processor or speakers, First you have to check the audio output from the processor by using another external amplifier... connect it to the correct audio out pin of processor( these are R,L audio written in pcb near the processor lead that carry) if there is sound moreover than 45 minute....... replace the external amplifier and connect it to its own amplifier.... disconnect the own cabin speakers and connect another sp. and check... if there is sound break after45 minute.... replace the amplifier ic(may beTDA7297) if there is still have the problem, check the amplifier circuite suitable for your ic and dissconnect the mute connection from processor and make a connection to the +ve or ground follows as the circuit(means give external mute signal to amplifier dont from processor)......

If sound when a DVD the set is ok.

Look:

Is sound turned down on set or muted and same for a cable or sat box if used for signal.

In menu are speakers turned off or on?

If set has hookup for external speakers is it switched to internal or external.

A setting in the set or the box used is causing this as the set is not smart enough to know when you are playing a DVD or just watching TV.

triple check all connections from box and in the set.

Generally when the head phone jack is inserted the speakers will get disconnected automatically.

If you are going to use external amplifier you can try the AV sockets. Opening the TV you may require the special screw drivers some times.

have you tried going to start then go to control panel then go to sounds and audio devices and look to see if the internal speakers are turned on. most pc's will turn them off when they see external speakers pluged in then when you unplug the speakers you have to go these steps to fix the problem.

Quick description as per ICOM Manuals:
Quote
The AF amplifier circuit amplifies the detected signals to drive a speaker. The AF circuit includes an AF mute circuit for the squelch. AF signals from IC1 (pin 9) are applied to the de-emphasis circuit (R61, C89). The de-emphasis circuit is an integrated circuit with frequency characteristic of –6 dB/octave. The integrated signals pass through the high-pass filter (Q5, R62–R67, C90, C91) to suppress unwanted lower noise signals. The filtered signals are applied to the AF mute circuit (IC7B), and then passes through the [VOLUME] control (VR board; R1) via the “VOL1” signal. The signals are applied to the AF power amplifier (IC6, pin 1). The output signal from IC6 (pin4) drives the internal (external) speaker.
Unquote
I thus assume the IC you are looking for is the IC described as IC 6.
Data sheet availible online: http://www.datasheetcatalog.org/datasheet/sanyo/ds_pdf_e/LA4425A.pdf
The IC is a Sanyo LA4425A. A 5W Power amplifier.

Hi, Please update Sound driver from Hp.com and try
If you dont have any control on Quick launch buttons to turn on Volume, update Quick launchdriver. If that does not fix the issue, if you have to replace Speakers on the laptop

That is not a software problem.
The headphones/external speakers jack socket has a switch to exclude from audio the internal speakers, when a jack plug is connected.
This is a very simple device and is not software controlled.
The fact that it has gone faulty at the same time you reinstalled the system is a coincidence.
If it does not mute when you insert headphones, all you can do is trying to play with the jack plug , inserting and pulling it out. If this does not unlock the switch, the alternative is having the jack socket replaced by a technician. This is generally an expensive repair, asthe socked is soldered on motherboard.
A cheap alternative to a proper repair is using an external USB to Audio Adapter and mute the internal audicard when using headphones.