My VDF speed fluctuates often

[JamesPiechota]

Assuming you are using the Team’s VDF server, it is normal. VDF servers can only compute VDF, anything else running on the server will slow down the compute and increase your VDF time (and slow down your hashrate).

If your VDF changes often, and also shows Undefined frequently, you may have a network congestion issue.

See the VDF guide for more information on VDF.