Looked like an issue with my radio. The radio showed high SWR and the external SWR meter showed no issues. Checked everything including disassembling and reassembling the yagi. Was tired and fedup so decided to not continue. Was a good decision. Problem turned out to be the one cable I did not check. If I continued fiddling I might have damaged the radio! Especially as I was too tired to pay proper attention to what I was doing. As usual, the cause of the issue was obvious in hindsight.