During July 2025, mfcc64 focused on stabilizing the FFmpeg/FFmpeg repository by addressing a critical bug in the showcqt filter related to audio processing. They identified and fixed an unbounded copy index in the fft_data path, ensuring indices remained non-negative and preventing crashes or corrupted output under edge-case time parameters. Working in C and leveraging deep knowledge of FFmpeg’s avfilter internals, mfcc64 improved the reliability of audio visualization workflows, particularly under low timeclamp or FPS values. This targeted bug fix enhanced data integrity and runtime stability, demonstrating careful reasoning about data paths and a strong command of bug fixing in complex systems.