Volume type is set to media when call is initiated

### Steps to reproduce

- Initiate a call
- Press volume buttons, adjust Call volume. Nothing happens
- Adjust Media volume, hear volume change

This does not occur when joining a call, only when I'm the one starting the call. I've verified that this occurs on two different devices. The volume buttons do still try to adjust call volume, not media volume, when this occurs.

### Outcome

#### What did you expect?
Volume of call to be adjusted when call volume is changed

#### What happened instead?
Volume of call is only changed when media volume is changed

### Your phone model

Pixel 8 Pro / Galaxy A52s 5G

### Operating system version

Android 16 / Android 14

### Application version and app store

25.09.0

### Homeserver

Synapse 1.136.0

### Will you send logs?

Yes

### Are you willing to provide a PR?

No