It had come to the attention of the employees that the police were on the verge of finally apprehending the elusive Scranton Strangler. Whereas the whole office, including Michael, were interested in watching the broadcast, Gabe was in disagreement with how work time was being spent. This cold opening established a good foreshadow for the rest of the episode, as it outlined the differences in management that Michael and Gabe have.
Michael has always had a problem with authority. He has been shown to defy the people above him constantly, by stubbornly preferring to do things his own foolish way. The combination of his own stupidity, resentment of other people's success, and exploitation of his position as regional manager have all resulted in him using authority to buy social acceptance. This also means that he does not just have problems with authority above him, but also in being the authority in a proper manner to the people below him.
Back in season two (in "E-mail Surveillance"), Jim threw a party, and he deliberately did not invite Michael. Nobody missed him. Viewing Party explained why. After Kevin referred to Gabe as the boss, this effortlessly aggravated Michael into jealousy. Instead of just enjoying the Glee party, Michael found conflict with Gabe in tossing pizza dough, and in fighting over the volume. However, Michael's influence at a party is significantly less than what he usually wields at work. Michael was forced to face the true consequence of his actions, in that he isolated himself from others out of his own volition, making his fear of loneliness a reality. But he did not just stop there. He went one step further, by physically sabotaging the outdoor cable connection, as to take away the episode of Glee for everybody to enjoy. Once again, Michael made it all about himself. He ruined another party and pushed people further away from him all in one evening.