Hi Jayg74,
To help us isolate where the sounds originate, are you able to turn off the charging case sounds to help us determine if this is the alert you're noticing? This resource will show you how: Change settings for AirPods Pro (all generations) - Apple Support
"Turn off charging case sounds on AirPods Pro (2nd generation)
Your AirPods Pro (2nd generation) charging case plays a sound when it pairs, charges, and more. You can turn off these sounds.
- Wear your AirPods, and make sure they’re connected to your device.
- Do one of the following:
- On iPhone, iPad, or iPod touch: Go to Settings , tap the name of your AirPods near the top of the screen, then turn Enable Charging Case Sounds on or off.
- On Mac: Choose Apple menu > System Settings, click the name of your AirPods in the sidebar (you may need to scroll down), then turn “Enable charging case sounds” on or off"
If you still need help in identifying the sounds, you may consider reaching out to Apple directly here: Contact Apple Support
Kind regards.