Multichannel USB Audio not working on Google Pixel 9 Pro

Android version(s): 15
Android device(s): Pixel 9 Pro
Oboe version: Oboe v.1.9.2
App name used for testing: Oboe Tester,(91) v2.7.2

**Short description**
Multichannel audio (i.e. channels beyond the first two) does not work on Google Pixel 9 Pro with Android 15.

**Steps to reproduce**
Connect a USB Audio Device with 4 output channels (see list of tested devices below)
Open Oboe Tester
Select Test Output
Select device
Select 4 Channels
Open
Start

**Expected behavior**
Signal from all Outputs (0,1,2,3)

**Actual behavior**
Signal only from Outputs 0,1, silence on Outputs 2,3

**Device**

Denon DJ DS1
AlphaTheta / Pioneer DJ DDJ FLX2
AlphaTheta / Pioneer DJ DDJ FLX4
AlphaTheta / Pioneer DJ DDJ GRV6