Dynamic Compression is a form of audio compression used in Video Games Awesome that Fraser usually shouts the name of to tell if its working. The compression helps balance the audio levels of the show to let the hosts do the screaming they love most at a tolerable volume. Whenever a particularly loud sound occurs, the chatroom will usually light up with "DYNAMIC COMPRESSION!".
Due to the the fact that Fraser continues to do this for the purpose of causing annoyance and not just for testing, this could be labeled as a form of trolling.
Unfortunately there are no videos of Fraser doing "DYNAMIC CIMPRESSION" as he typically does this as part of the pre-show. Therefore the only way to see it is to watch a show live.