Internet is rapidly growing because it offers the easier and interconnected digital lifestyle. The growth also brings data security threats. Data are used to be protected by encryption. Encryption morphs the data into unreadable series of code which obey a certain rule. But the way encryption did to the data make the existence of precious data is exposed to danger. Steganography which differ from cryptography offers a stealth data protection without make any suspicion to the existence of data. Steganography hides the data through images, audio files, TCP/IP, etc. Phase encoded steganography is a robust information hiding method on audio file. It is because the ability to deceive human auditory system perception. Exploiting the insensitivity of human auditory system to distinguish a slight phase difference, interaural phase encoding sound modification turn out to be undetectable. Utilizing the base-4 and hexadecimal code number basis, instead of binary, embedded data capacity can grow significantly. At 33 dB SNR, it is possible to embed 1500 bit data per second. The higher code number base and the higher number of segmentation, the more minimum modification would happen on time domain. These base-4 and hexadecimal encoding are quite robust against attack based on amplification and filtering.