Decklink 8k Pro lost audio and video shift bug

When using Decklink 8K Pro for multi-channel independent, if the signal not all the same clock reference, or not all 4 inputs in connected, it will cause the sound disappear after some seconds. And the sound only way to recovery is need to reboot system.

Here are the demo for only connect 3 SDI input from converter:

you can see after few seconds, the sound has disappeared.

And here is the demo for change the signal from ATEM switch to converter by using Videohub, you can see the sound signal disappeared after I change the signal source and for few seconds.

The same connection and signal are tested at Decklink Duo 2, they work perfectly.

Test Platform:
OS: Ubuntu 18.04 LTS
CPU: Intel I9-9900K
RAM: Cosair 8G * 4
GPU: NVIDIA Titan V
CaptureCard 1-4: Decklink 8K Pro
CaptureCard 5: Decklink SDI Micro

Signal Type:
3G-SDI Type A (also tested with 3G-SDI Type B, the same results)

Signal Source:
1*Blackmagic Design HDMI to SDI 4k
1*ATMOUS SHOGUN
4*MD-HX
1*ATEM 4K Production
1*Videohub 20x20

The test platform:

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Two Signal from ATEM:

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Two Signal from Converter:

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the signal from ATEM is almost same phase, the signal from converter is not at the same phase.

Updated:
I use Ref In to synchronize all the signal output from converter, and then the card can be work almost normally for abort 5 - 10 minutes without dropping audio signal, I think the signal Ref may be the key for this bug, hope BMD fix this problem ASAP.

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Updated

I found that the problem is only happen at Linux, but our application is required to run at Linux.
When using the Ref In, I have test for running over 10 hours without dropping audio, but the video has shifted, I am stilling finding any solution for fix this.

The before directly from convert's timing graphic:

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May be stable at most time timing graphic:

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The video shift problem I think may be because by ref source has jitter, and the card hold on wrong state to process the data.
Here are the video for the four channel timing from oscilloscope

The problem may be resolved by remove the card from system and sending PCIE reset request to the card, and then rescan the card without reboot the whole system, but sometimes may cause kernel fault, and required to reboot the computer, here are the log when the error has happened.
https://pastebin.com/2RGHrD5b

The sound disappear problem still exists on 11.2 drivers.

Have you managed to fix the issue with shifted video? I have encountered similar problem on DeckLink Quad HDMI Recorder. Right after start of the computer it works normally but after few hours the video is shifted similarly as displayed on your images. I am running Ubuntu 18.04 with kernel 5.4 and I have tried Desktop Video drivers 11.6 and 11.7.

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