—The quality of transmission is very important in digital communication. However, in non-deterministic environment or different transmission message signal, bit error rate of PCM encoding methodologies maybe be varied according to different working condition or different signal source. Theoretically, the bit error rate of PCM encoding methodology can be computed by either mathematical or statistical methods. The bit error rate is generally assumed as a constant value. The bit error rate is not deterministic in the real world. This paper proposes a dynamic PCM selector that can dynamically select an optimal PCM codec module. The system can dynamically switch to the encoding mode with possible lowest bit error rate, according to the current type of the transmission. By way of this design, it can greatly reduce the overheads of the error correction process. Keywords—PCM, Pusle Code Mudulation, BER, Bit Error Rate, PCM codec optimization, digital communication, speech encoding, soft IP...