Most in-class uses of audio and video are covered by the Classroom Use Exception and are just fine. Instructors (and students) can, without limitation, display and perform things in face-to-face teaching in a classroom setting at a non-profit institution. The only real restriction is that the video or audio you are performing or displaying must be a legally obtained copy.
The classroom use exception DOES NOT apply to online classrooms (either as part of a hybrid class or in distance education classes).
Remember: the classroom exception applies only to displaying and performing, not to copying and distributing.
Image credit: Courtesy of the Boston Public Library, Leslie Jones Collection.
As mentioned above, the Classroom Use Exception does not cover any kind of copying. So any digitizing of video and audio for the purposes of instruction would need to be covered by some other exception. Media Support will digitize media for instructors under certain circumstances and have a webpage that details a variety of scenarios.
The courts have not provided us with much guidance regarding the copying of audio/video for purposes of instruction. It is very likely that fair use would cover many cases of copying, especially within a non-profit institution like PCC. It is also certainly the case that not all copying of video and audio for educational purposes would qualify as a fair use.
If you are teaching a distance class, copying and subsequent posting of video and audio might be covered by the TEACH Act, if your use and the material meet all of the criteria.
image: "VHS-cassette" by Groink - Own work. Licensed under CC BY-SA 3.0 via Wikimedia Commons
"ITunes 12 logo" by Apple Inc. - Own work. Licensed under Public Domain via Wikimedia Commons -