It seems that you are having some issues with the SlingPlayer for Android Mobile devices, since the A/V signal is out of synch.
The fact that the connection through your computers works fine lead us to think that the issue is related only the the connection speed you use on your Mobile device.
Are you using a 3G connection? Is it the 4G connection? What is your current Mobile connection speed?
Make sure to include further details. This way, other forum users will provide you with accurate responses.