anyone can help me about sim900 module?, i can make a call to a mobile phone but my problem is on the mobile side, if i talk on the mobile, i can hear back my voice just like an echo of what i say... example i say 'hello' on my mobile, i also hear back the 'hello'. i adjusted the speaker volume to 25 and mic to 4 but still the echo is there. anyone can advise me?
the volume was adjusted via AT command, but the still i can hear the echo on the mobile phone..
I wan't a clean audio just like speaking from phone to phone