Etienne, problems were on both 4.0.5 and 4.0.8, we then used the beta release linked here: Software Beta Test Release which seems much better in terms of latency, lack of stuttering / dropped frames etc.
William, when we experience this, CPU is barely above 30% on any cores on the PC and GPU is about 35% (we run using a dedicated NVidia GPU). I’ll try it on a few other PCs here to see if it is machine specific. We have noticed that the latency issue seems to be exacerbated by using PingViewer at the same time but even then CPU and GPU utilisation remains low.