I can not hear the caller but he can hear me. I can hear only when I switch to speaker mode.

? Microphone? For the other person to hear you the microphone on the phone must work. You cannot adjust that. For you to hear them you need a speaker on your phone. You can adjust the volume of the speaker on your phone. If callers cannot hear you try putting your phone on the speaker, rather than handset mode so it becomes a speaker phone. Then, while talking to someone to test the phone, try holding it in different ways to see if you are covering the microphone with your fingers. Without knowing what model of phone (specifically) you have I can't figure out where these are located on your phone. You can google the model though and locate them yourself easily.

Maybe try plugging headphones into it. That will tell you if the sound is dead or not. Also, on a lot of devices, there is a speaker kill switch integrated into the headphone jack that may be dirty or just need to be moved a few times with your headphone plug. However, if the caller can't hear you, it may be the audio circuit of the phone has gone to be with other Samsungs in the sky.

its a headjack problem or speaker problem

hi,
It seems that the earpiece speaker in your phone might be not working.
Before that verify that the call volume is set to maximum while you are in a call. If still problem persists, then you have to check the earphone present in your mobile.
Please provide your ratings.
Thanks

Get A GOOD Phone

if you cant hear caller voice. do one thing go to gallery and go to voice recorder and record some voice then save that then go to media and play recorded sound if its working means your loud speaker is working but not ear peic means (ear speaker) not working. so then you need to change ear speaker.you can do your self just watch video on online.

Hi,

All the [hones contains two speakers,
1)Headspeaker, Used for hearing from callers..
2)Loudspeaker for hearing Ringtones and callers when on speakerphone mode

THe problem in your case is with the headspeaker,

To check the headspeaker:

UNSCREW THE PHONE TO INSPECT THE SPEAKER.
REPLACE IT, IF IT IS DAMAGED.
TRY USING SOLDERING LED AND SOLDERING IRON TO SOLDER, THE SPEAKER

leave me comment, if you need further assistance
RNJ VINODKUMAR

please check for the speaker volume in ur phone and if still continues speaker has to be replaced

mine does it from tme to time and so does my friends.....unusual solution but banging the phone on a table quite hard a couple of times really does the trick.

dear,
u can try to solve it by master reset. but most probably, it is a fault of your ear piece. u have to change it.
regards,