In multimedia conferencing, multi-point controlling unit (MCU) provides the capabilities to process audio, video and data stream for multi-point conference. The capability of audio processing is basic and requires more for real-time criteria. This paper categorizes and analyzes the schemes, and a new multi-point speech audio mixing scheme using align-to-self weighted algorithm is provided to meet the demand of the practical need of multi-point speech processing. By applying the adaptive mixing algorithms, these high-performance processing schemes do not use the saturation operation which is widely used in multimedia processing. Therefore, no new noise will be added to the output, and they have low complexity and good hearing perceptibility. In the mean time, the schemes are designed for parallel processing, so they can be easily implemented with hardware, such as DSPs, and widely applied in multimedia conferencing systems.