He really can't help but roll his eyes at the fact that Knockout is already being so belligerently disrespectful, but Starscream lets it slide for now.

"Why was I-- I thought you were an Autobot! And really, can you blame me? What sort of self respecting Decepticon would choose a land based vehicle mode over a flight capable one?" he gestured aggressively up and down at Knockout's form with his non-transformed hand.

"Besides which I've been sending out a constant encrypted distress signal for weeks now and received no response..." he growled with an accusing frown.