the cause is the encodier method. the mambox2 recognizes the mp3 only, if the bit rate a multiple of 32 kbit. thus 32, 64, 128, 256 kilobit/sec. the samplerate must be 44100 hz!!
the player on your site is runnig fine for me. can hear the music (ie and firefox). my player is the previous version. this functions perfectly, exactly, like yours :-)
which browser do you use??
the cause you will find where differently, not with mambox.
check your internet option
toos-->internt option-->advanced
enable third-party browser extension
then
enable play sound in webpages more ideas i do not have unfortunately.
Re: I Need HelpWith Mambox 
Linear Mode
