Worked on the androidx/media repository to enhance CMCD (Content Metadata) management for media playback applications. Developed a configuration option allowing CMCD to be disabled at runtime by returning null from the configuration factory, providing greater flexibility and control over analytics data transmission. Addressed a critical bug to ensure that no CMCD data, including playback rate values, is sent when no keys are permitted, thereby preserving data integrity. Expanded test coverage to validate both configuration-based enabling and disabling of CMCD, as well as edge-case handling. Utilized Java and configuration management skills, with a focus on ExoPlayer integration and network protocol compliance.