UserAgent: Mozilla/5.0 (X11; Linux x86_64; rv:64.0) Gecko/20100101 Firefox/64.0
Platform: 11021.56.0 (Official Build) stable-channel hana

Steps to reproduce the problem:
1. Start capturing audio, such as with pp::MediaStreamAudioTrack.
2. Configuration says sample rate is 48000 Hz.
3. Receive buffers normally.
4. Play any normal YouTube video to have regular audio.
5. Start playing a video file with 44100 Hz audio track.

What is the expected behavior?
Continue to receive 48000 Hz audio buffers.

What went wrong?
Received audio buffers claim to be 960 samples of 48000 Hz, but it's actually 960 samples of 44100 Hz sampled audio. This is reflected in the timestamps being 10.9ms (480/44100 * 1000) apart instead of 10ms, only receiving about 90 buffers per second instead of 100, and playing back the buffers at 48000 Hz has the pitch shifted higher, but forcing playback at 44100 Hz sounds mostly normal.

Did this work before? N/A 

Does this work in other browsers? N/A

Chrome version: 70.0.3538.76 (Official Build) (32-bit)  Channel: stable
OS Version: 70.0.3538.76 (Official Build) (32-bit)
Flash Version: 31.0.0.122

Version information above is for a Lenovo N23 Yoga (hana), this also happens on a second ARM Chromebook, a Samsung XE303C12 (daisy). Can't get it to happen on any Intel Chromebooks.

In fact, it's also reproducible with Chromecast! The audio playback is higher pitched and constantly skips (since it's expected 48000 Hz). Here's a recording: https://streamable.com/i6kb7

Audio playback on the actual device continues to sound normal.

I'm not 100% on the combination of videos to play, usually takes a few tries, but once it happens it can stay in this state for as long as audio is playing. It's also easier to get to happen after a fresh reboot.