How to increase speaker volume of HTC Evo 3D I have just bought HTC Evo 3D and as much I am inspired by phone, its speaker performance is giving me equivalent dissatisfaction, the speaker sound is very low for ringtone as well as for music playback. Hardly can hear sound if its kept in another room. I have done few workaround example installing volume+ and also downloading loud ringtones. But no difference, is it possible I can increase its speaker sound.
Thanks
This method can be used to increase the maximum speaker output on your HTC EVO 3D, but bare in mind, if you set the output level to high, it might be possible to blow out your phone's speakers.

Preparation

Note that this method uses software only available for Windows.


Install HTC Sync on your computer.
Get your 6-digit MSL code, using one of this two methods:


Androidforums: Easy way to get MSL without calling Sprint or using CMDA Workshop. You will need to install aLogcat (free from Google Play Store)
XDA Developers Forum: Retrieve MSL CDMA Workshop Method.

Install Qualcomm Product Support Tools (QPST).




Connecting to the Phone and Adjusting your Levels


Put phone into Diag mode:

dial this code: ##diag#
Start the QPST service programming:

Access your start menu, select the "QPST" folder, then "Service Programming".

If your phone was successfully set to diag mode it will be listed on the first screen. Select it and press ok to continue.
Press Read from Phone to connect to your phone and enter the code obtained from the second step of your preparation process when solicited.
Click the Sounds tab:

Change each level to whatever you want it to be. Level 4 is the loudest
After the necessary adjustments, press Write to Phone.

Some read errors may be presented, don't worry, its normal.
Writing process is done, reboot your phone and try the new settings.






Credits to XDA Developers forum thread: How To Use QPST to INCREASE the volume on the Evo 3D.

Some issues are discussed on the thread if you run into trouble.