1. Compatibility Issues: Not all email clients support audio files, which can lead to inconsistent user experiences. 2. Increased Load Time: Adding audio files can make your email larger, potentially leading to slower load times. 3. User Annoyance: Auto-playing music can annoy some users and lead to higher unsubscribe rates. 4. Accessibility Concerns: Not all users may have the ability or desire to listen to audio, making it essential to provide a text-based alternative.