When an iOS device is connected to a Bluetooth accessory that utilizes the Hands-Free Profile (HFP), we are encountering an incorrect audio routing behavior specifically for system notification tones.
Accessory Connected: The iOS device is successfully connected to a Bluetooth accessory (specifically, a WM500 device) using the HFP profile for voice communication.
Voice Audio: Audio streams related to phone calls or voice communication (using the HFP/SCO link) are correctly routed to the WM500.
Notification Tones Issue: System notification tones, which are played using the tonetype.systemsounds API, are not being routed to the connected HFP accessory (WM500). Instead, they are incorrectly played through the iOS device's built-in speaker.
This causes a poor user experience, as critical application alerts and system notifications are missed when the user is relying on the connected HFP accessory for all audio output.