[arnehormann]

TCP and UDP use the same underlying wire and the same hardware. If UDP would lose a packet or it would arrive late, the same could happen to TCP. TCP will retransmit and you lose a little bandwidth. But in both cases, you can't use the late data anymore - audio has about the hardest timing restrictions you can have when dealing with humans. Lateness means forced loss. TCPs ACK packets don't help there either, you want to keep down latency because your data can not be used any longer if it's dropped or late. Reliability becomes increasingly irrelevant, latency is everything.