Will the REAL STL IP Please Stand Up... AudioTX STL-IP, Reliable Live Audio over IP for STL, Programme Distribution and live Studio Connectivity over IP Networks and the Internet - AudioTX STL-IP Plus. A robust, broadcast-quality IP codec solution for low delay audio over IP. AudioTX STL-IP is a 1U unit with professional balanced analog and aes/ebu digital inputs and outputs and only 5ms delay, from MDOUK.