The Samsung GT-S 5230 mobile phone allows users to access test mode for various operations such as increasing or decreasing the volume on their phone amongst other features. If the volume of the MP3 music being played on the phone is very low, the test mode can be used to increase the volume of the Samsung GT-S 5230 mobile phone. A specific number sequence must be typed in the mobile phone to provide access to the test mode and commands. The APVMXGAIN can be used to increase the volume of the mobile phone. The test mode displays a list of volume levels that can be chosen manually.
If the volume of your MP3 is too low on your Samsung GT-5230:
On the keypad, dial *#0002*28346# (to access test mode)
5 Common Config.
5 APVMXGAIN MP3.
Press on 0 (zero) and and you get a notification "READ WRITE".