i have had the same issue all i did was hold on to the up button for about 5 secconds and when i let go my media and sound was workingg just fine. if that does not work all u have to do is just turn it off for about 1 or 2 minutes and and then turn it on. press up on the volume button until all the volumes are on the highest they can be then press the settings button next to the volume then you will see that the volume that was not working will be working much better.