Audio encryption is important to keep private and sensitive information secure during transmission. In this paper, investigates audio encryption based on hyper-chaotic signals. Also, studying and analyzing the impact of frame and sub-frame length on the security, real-time performance, and bandwidth requirements of a secure audio communication system employing hyper-chaotic scrambling. The hyper-Rabinovich chaotic system (HRCS) utilizes four state vectors and five parameters to scramble and hash audio signal subframes within each frame. The simulation results demonstrate a direct relationship between frame length, security, and real-time performance. Increasing the frame length enhances security but diminishes real-time performance. Similarly, subframe length influences both security and bandwidth. Smaller subframes improve security but increase bandwidth requirements due to the resulting expansion of the encrypted audio signal bandwidth. From a security perspective, the proposed hyper-chaotic scrambling achieves a segmental spectral signal-to-noise ratio (SSSNR) of − 2.8565 dB when the subframe length is two samples and − 1.4812 dB when the subframe length is eight samples. In addition, the proposed system exhibits a high key space of 2598 keys. The findings of this study provide valuable insights into the trade-offs between security, real-time performance, and bandwidth in hyper-chaotic scrambling for secure audio communication.