A particular application of audio data hiding systems and watermarking systems consists of using the audio signal as a transmission channel for binary information. The system should ensure a reliable and robust transmission for various channel perturbations but also propose a low computational cost for real-time applications. In this paper we present a hybrid spread-spectrum data hiding system, which combines two reference systems taken from the State-Of-The-Art: the one based on a real-time receiver and the other one based on an informed embedding strategy with maximized robustness to additive perturbations. Experimental results permit to assess the efficiency of the system in terms of: (1) transmission reliability, which is significantly improved compared to reference systems, and (2) computational costs, which allows for the feasible real-time reception process of broadcast applications with off-line embedding.