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Quest Pro Passthrough lag/latency/low framerate over Oculus Link cable
The Quest Pro passthrough video feed lags considerably when entering Play mode in Unity and using the Link cable. Virtual objects render at > 72 FPS (reported in Stats window), but the video underlay from the real world feels like ~3 FPS. Additionally, the passthrough often does not work at all over the Link cable---specifically, if I remove the headset after running the scene (but leave the device plugged into the Link cable), the next time I put the headset on and run the scene results in no passthrough video (black background) or a warped still image of the passthrough video that does not change as I move/rotate my head. The tedious fix for this issue has been disconnecting and reconnecting the Link cable, and then re-enabling the Link in the headset.
The same scene works fine (consistent, no passthrough lag) using a Quest 2. I am using a desktop computer with an RTX 3090 and a USB 3 connection with >2 GB/s throughput.
As indicated in this post the passthrough works fine when deployed to the device as a .apk. However, I have not been able to find a solution for running it in a usable fashion over the Link cable. One of my colleagues is having the same issues in Unreal Engine.
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I have exactly the same issue and this makes our desktop app and development extremely hard if not impossible.
Has any fix been found?
Any update on this? I've also been seeing very slow framerates on the passthrough video on the Quest Pro when using Link. I don't remember seeing this issue when the Pro first came out... seems to be something newer in the past few months. Issues doesn't occur when running natively on Android.
This issue also appears in Unreal Engine (5.0, 5.1) with the Quest Pro, really hoping to see a fix soon. Passthrough for desktop apps is impossible to use, so the entire mode is not possible to build with for even native Quest Pro apps without building to the device with each change.
This makes it impossible to develop passthrough applications using Unity. ://
Have you managed to solve this in any way please? It's horrible to work on anything through Unity!
The passthrough performance for me has been better in recent days. I'm not exactly sure what fixed it, but I think it might have been these things:
1) The quality of the USB-C cable is crucial. If you're using a low quality USB-C cable, it won't be able to handle the bandwidth of the passthrough video feed.
2) The kind of USB-C port on your computer might(?) be important. I recently learned that not all USB-C ports are created equal! Essentially, you'll want to look to see if your computer has a USB-C Thunderbolt type of port. These ports are capable of 40 GB/s compared to the 20 GB/s of typical USB-C ports. For more info on that, see https://www.westerndigital.com/solutions/thunderbolt-vs-usb-c
Although the passthrough video framerate has been better is recent days for me, it's still not as good as when I'm running natively on the headset. But hopefully these tips may help you.
