As I understand it, you observe some issue with you VIP link. To ensure we are on the page, just would like to check with you on the following:
1. What is the device that you are using?
2. What is the Quartus version that you are using?
3. Are you observing issue in hardware/simulation or both?
4. To facilitate further debugging, it would be great to create a simple test design with Test Pattern II->Frame BufferII->Clocked Video Output, then perform Modelsim simulation to see if similar issue observed? This would be helpful to narrow down any functional related issue.
Please let me know if there is any concern. Thank you.
As I understand it, it has been some time since I last heard from you. I would set this case to closed at this moment. Feel free to file a new case if you have any further question related to this request. Thank you for your understanding.