code: public void addPayloadType(final PayloadType pt) {
          synchronized (payloads) {
              if (pt == null) {
                  LOGGER.severe("Null payload type");
              } else {
                  payloads.add(pt);
              }
          }
      }
docs: Adds a audio payload type to the packet.
  
  @param pt the audio payload type to add.