1873199 - External (stereo) microphone on Android distorted

Status: NEW

(Core :: Audio/Video: cubeb, defect, P3)

Description

[Andreas Pehrson [:pehrsons] (PTO; back in Jan)]

STR:

1. Connect an external (stereo) USB microphone to an Android device. In my case a Deity VO-7U on a Samsung Galaxy S22.
2. In Firefox open https://jsfiddle.net/pehrsons/r78o053g/show.
3. Load the fiddle (if on headphones, disable all three checkboxes to get raw audio) and click "gUM Audio plain" and approve the capture.
4. Say something and listen for the loopback audio, ideally on headphones.

Expected:
Voice sounds good.

Actual:
Voice is distorted. To me it sounds like mono audio interpreted as interleaved stereo before being played. I suspect any stereo input would reproduce this.

Voice sounds good in Chrome with the same setup.

Comment 1

[Paul Adenot (:padenot)]

Andreas, logging should make this clear:

adb shell am start -n org.mozilla.geckoview_example/.GeckoViewActivity --es env0 MOZ_LOG=cubeb:5,MediaTrackGraph:4

using GeckoView example.

Comment 2

[Andreas Pehrson [:pehrsons] (PTO; back in Jan)]

Attachment: logcat with cubeb:5,MediaTrackGraph:4 covering audio session of STR

Comment 3

[Paul Adenot (:padenot)]

Looks like we're not reading enough input frames. We should try increasing the latencies.