Livestream audio can sometimes be very difficult to hear. There are a number of factors that may contribute to this. Occasionally there are problems in the sanctuary with microphones that are muted or speakers that are out of range. In theory all of those things are tested ahead of time. The worship tech team does a sound check with every microphone every week to minimize those glitches.
It is also possible to have audio problems on your end, with your computer or speaker systems volume controls. Here are a few things to check every time you play the livestream: