Hyper-V Application Issues

So I have moved a client from an old HP server to a new HP Gen 11 server running Server 2022 and Hyper-V.

Everything is patched and running the newest firmware releases from HP>

In the VM running server 2022 there is an application that runs very slowly when moved to the new hardware.

We can not find the cause of the issue, but once moved back it runs fine.

A new VM was created to run the application and it was the same.

Everything else is fine and running as expected.

If anyone can suggest what the cause could be?