Genesys Cloud allows customization of hold audio for in-queue call flows through the Architect interface. Users can select, edit, or create new audio prompts that callers hear while waiting in queue. The configuration process involves accessing the Flows menu, selecting In-Queue Call, choosing the default in-queue flow, and navigating to In-Queue settings. Through the Hold Music list, users can either select existing audio prompts or add new ones, though editing capabilities may be limited for system prompts, particularly regarding name, description, and TTS modifications.