Sound Problems



When people experience sound problems with there phone, they commonly confuse the speaker with the microphone.

SPEAKER problem- If you cant hear sound from the phone, or if the sound is distorted, the problem may be with the speaker.
MICROPHONE problem- If you can hear sound on your phone but nobody can hear you, the problem is the microphone.

Speaker problems:
If your speakers sound is distorted, chances are that its a blown speaker that is causing the problem.

All phones have at least two speakers, the internal speaker and an external speaker. The internal speaker plays at a much lower volume then the external speaker, so when you press your ear against the phone, it doesn't hurt your ear drum. The external speaker is much louder, because its used to grab your attention by ringing loudly, and also when the speaker phone option is used.

Some phones have both the internal and external speakers attached in a single module, however most phones have two separate speakers (see images below)










Notice the VX8100 speaker (left hand side), you see two wires running off it, so you know its a single speaker. Now look at the VX6100 speaker (right hand side)- notice you can see four wires running off it, indicating two separate speakers are connected together. If a module speaker fails, the entire module has to be replaced. For example if the internal speaker fails, you still have to replace the external speaker since the module can not be taken apart.


If your phones speaker doesn't produce any sound at all, you should especially consider sending your phone in for service rather then ordering a replacement speaker, because if you cant hear any sound at all, its possible that the problem is another component blocking the circuits connection,

This image shows what a phone looks like with the plastic covers removed. The red lines represent the audio circuit.

During normal operation, energy is carried from the circuit board, to the flex cable, to the LCD module, and finally up to the speaker.

If anything in this circuit is damaged,no sound will be produced.











Intermittent sound problems:


If your phone has intermittent sound problems, chances are that something within the sound circuit is damaged, usually the flex cable. The sound signals originate from the phone's circuit board, and are passed from chip to chip, to the flex cable, to the LCD module, and up to the speakers. So if the audio chord in the flex cable gets ripped, even if you replace the speaker you still will not have any sound. Flex cables develop very small cracks in the cable edges over time. If the phone is dropped, or opened and closed to many times (flip phones) then the cable is subject to wear and tear, which can cause a partial cracking of the cable. The flex cable transmits lots of data to and from the circuit board, including sound, display (screen), and often times the vibrator.



















A flex cable is composed of a series of cables sandwiched together making a single cable. Underneath the ground cable (usually the top layer of the cable) you can see the individual strands. Above you can see that a tear has formed, cutting three individual strands. When you open the phone, small amount of tension is placed on the cable, and the cable may shift slightly. If the cables that were cut are part of the audio circuit, then as the phone opens and closes, the sound may be produced intermittently as the cables make contact briefly. As the phone is opened and closed, the tare will get larger, and eventually other functions will stop working, like for example the LCD module.

So if you cant hear any sound at all, you should consider mailing in your phone for service.


Microphone problems:
Over time the phones internal microphone can fail, preventing sound from being transmitted. In this case, you can hear the person talking to you, but the other person can not hear you respond. If your microphone is not functioning properly, this may actually be an easy fix, depending on the type of microphone.


plugin micPlug in component - This type of microphone can be replaced very easily (no soldering required). It just fits into the microphone grooves on the inside of the phone, and when the circuit board is placed on top of the microphone, a circuit is formed. *If the phone is often dropped, the screws holding the phone together may loosen, or the mount that holds the screw in place may actually break. If that happens, you will not have a tight connection, and the signal will not be passed from the microphone to the circuit board, causing your voice from being transmitted.. If that's the case, simply re tightening the screws and that may fix the problem.



lg micmountable component - This type of microphone has a small cable mounted to it. The cable gets soldered to the circuit board. The solder secures the module in place. This is the most common type of microphone used in phones (with the exception to Motorola).





motorola micSurface mount component - Lots of newer phones (including most motorola phones) use these type of microphones. This type of microphone requires professional installation. because it is mounted directly to the surface of the circuit board. Removing the original microphone is the most difficult part since it has to be heated from the bottom, and you can not damage any other surrounding micro chips mounted to the circuit board. When installing the new one, it has to be soldered directly to the surface of the board (you cant simply press the solder iron against the microphone and wait until the solder melts, because by time the solder melts, the microphone would be damaged). To remove and reinstall this type of microphone, a hot air gun is required. We can professionally replace your surface mount microphone, mail your phone in for service

Need a repair?

Whether you want to repair your phone yourself and you only need a replacement part, or whether you want to send your phone to us for repair, email us with the make / model number of the phone (ex. LG VX6100) and we will let you know what type of component it is, and the price. Or you can mail your phone to us.