For MP3 audio over HLS you should be using 128kbs, 44100hz stereo. AAC is a better choice as Android does not support MP3 as for as I am aware.
Can you re-start Wowza in stand-alone mode [install-dir]/bin/startup.bat|startup.sh. This will open the console window and log server events, errors and warnings to the console.
If nothing stands out in the output, you may decide to open a ticket with the support team. To do so please zip your /conf and /logs folders. Send these along with a screen capture of your encoder settings, a link to a sample stream for testing and a link to this thread as a reference.