No sound with 10 or 12 channel USB device

[hendrik-algoriddim]

Android version(s): 14 (Build number AP2A.240605.024)
Android device(s): Google Pixel Fold
Oboe version: 1.7.2
App name used for testing: OboeTester v2.3.7

Short description
USB audio devices with 10 or 12 output channels don't output any audio

Steps to reproduce

• Connect USB audio device with 10 or 12 output channels (Allen & Heath Xone:96, Reloop RMX95, Rane MP2015)
• Open OboeTester
• Select "Test Output"
• Select device
• Set channels to the number of channels the device offers
• Press "Start"

Expected behavior
Sine Wave Test signal is played on all channels of the device (or a respective subset according to toggled channel checkboxes below).

Actual behavior
No audio output (silence).

Device

ro.product.brand = google
ro.product.manufacturer = Google
ro.product.model = Pixel Fold
ro.product.device = felix
ro.product.cpu.abi = arm64-v8a
ro.build.description = felix-user 14 AP2A.240605.024 11860263 release-keys
ro.hardware = felix
ro.hardware.chipname =
ro.arch =
| grep aaudio = [aaudio.hw_burst_min_usec]: [2000]
[aaudio.mmap_exclusive_policy]: [2]
[aaudio.mmap_policy]: [2]

Additional Info
Devices with 4 output channels work flawlessly (Denon DJ DS1, Novation AudioHub 2x4). We found no devices with 6 or 8 channels, so we suspect issues arise from somewhere between 5 and 10 channels.

[flamme]

Thanks for filing the bug, Hendrik!

Could you share if the USB devices more than 8 channels you tested only have one single profile? Or do they have profiles that support channel count lower than 8?

[hendrik-algoriddim]

I checked the OboeTester device report for all mentioned devices and they all displayed just a single channel count. Here are the exact results for the output devices in case there is any other helpful information in there. Please let me know if there is more I can do to help!

==== Device =================== 55
Id: 55
Product name: USB-Audio - XONE 96 USB 1
Type: USB device
Is source: Yes
Is sink: No
Channel counts: 12
Channel masks:
Channel index masks: 4095
Encodings: 2 4 22
Sample Rates: 48000 96000 44100 88200

==== Device =================== 85 
Id: 85
Product name: USB-Audio - Reloop RMX-95
Type: USB device
Is source: Yes
Is sink: No
Channel counts: 10
Channel masks:
Channel index masks: 1023
Encodings: 4 22
Sample Rates: 48000

==== Device =================== 95
Id: 95
Product name: USB-Audio - Rane MP2015
Type: USB device
Is source: No
Is sink: Yes
Channel counts: 10
Channel masks: 737532
Channel index masks:
Encodings: 4 22
Sample Rates: 48000 96000 44100

==== Device =================== 109
Id: 109
Product name: USB-Audio - DS1
Type: USB device
Is source: No
Is sink: Yes
Channel counts: 4
Channel masks: 204
Channel index masks:
Encodings: 2 4 22
Sample Rates: 48000 96000 44100 88200


==== Device =================== 124
Id: 124
Product name: USB-Audio - Audiohub 2x4
Type: USB device
Is source: No
Is sink: Yes
Channel counts: 4
Channel masks: 204
Channel index masks:
Encodings: 4 22
Sample Rates: 48000 96000 44100 88200

[flamme]

Thanks for the information!

It looks like the device can be connected, that indicates the device may have more than one profile. Internal bug 293311883 tracks the effort for fixing this problem.