May 22, 2017
I just found an article that discusses the audio - video lag when using Bluetooth.
I think the first paragraph is most relevant.
There’s been a lot of talk of wireless earphones lately, mostly due to the removal of the headphone port on the iPhone 7. I love wireless earphones, and for the most part I think their pros outweigh the cons significantly. However, they have one particular problem that really needs to be fixed.
I’ve used Bluetooth earphones and speakers regularly for about six years, on various different platforms. Generally, I’ve found that they perform well when playing audio, but depending on the OS, video can range from perfect to unwatchable. This is due to sync issues caused by the latency of the Bluetooth audio stream. If the OS simply starts the video and audio at the same time, the audio will lag behind by the length of time it takes the Bluetooth hardware to receive, process and output it. This can be compensated for, basically by starting the video stream a little later than the audio. In my experience, iOS and macOS handle this pretty well; whatever calculations Apple uses to coordinate the starts of the video and audio streams works most of the time.
Let me encourage you to roll back the firmware to version 1.06 at http://btu.bose.com
It doen't take long, and we'll have more information.
Jun 5, 2017
Hmm so weirdly I thought I'd try a full reboot of the QC35s before downgrading the FW - and (so far at least), the lag doesn't seem anywhere near as noticeable - TBH if I didn't know better I'd say it was back to where it was with the original FW! I'm going to keep an eye on things on a trip this weekend and see how it goes but it would be great if so!
I"m sorry that you're having a problem with this delay while watching a video online.
Based on ediflyer's post above, it sounds like it's worth rebooting the QC35. Here's how.
Does that make a difference?
Jun 9, 2017
I too am experiencing BT audio lag whenever I am streaming video. This primarily happens when using netflix on my Windows 10 PC.
The basic specs are as follows - and I can provide more detail if required.
Lenovo Carbon X1, 4th generation, Windows 10 Pro 64-bit, latest BT drivers installed.
Browser: Chrome 58.0.3029.110 (64-bit), or Microsoft Edge 40.15063.0.0
Bose QC35 with firmware 1.2.10
Let me know what else is required.