The Ultimate Doom: Brainwash (1) - S1-E5
Audio problem: When the Decepticon jets attack the maharaja's palace at the beginning Thundercracker speaks with Skywarp's voice. Later, at their base when the fake Optimus comes out Skywarp speaks with Starscream's voice.
Answer: This was actually one of many errors in Transformers, the Constructicons MUST have been built on Cybertron, the only transformers genuinely built on earth were the dinobots, reason being Vector Sigma has to give personalities to each and every robot, else they end up like the dinobots, very simple and dumb. For reference watch the episode "The Key to Vector Sigma" which introduces the Stunticons and Arielbots - both Megatron and Optimus Prime have to go to Vector Sigma to get decent personality traits installed, prior to this the new robots are controlled by remote controllers and have no AI.