I just received my new MacBook Pro 2019 16" (8x 2.3 GHz/32 GB/8 GB 5500), it's running the latest macOS Catalina 10.15.2 and the latest Resolume Arena 7.1.0.
Even with a single Lines generator I have a very noticeable "pumping" in the framerate of the final output. It's not really stuttering or skipping frames, more like someone was constantly modulating the master speed, slowing down the whole composition and bringing it back up at a rate of 1-2 times per second. Internally, the comp is running at a rock solid 60 fps and in the preview and advanced output windows the effect is not visible. Also it's not visible when I use the internal display as an output.