777 HDG SEL does not always work right

[JSACKS 0]

Sometimes after takeoff, after I have engaged the AP and hit HDG SEL, the yoke turns visually in response to a different hedg than the runway departure hdg, but the aircraft does not actually turn at all, it continues straight ahead as if nothing had been touched on the MCP. The only way to rectify this anomaly it seems is to momentarily disconnect the AP and then the aircraft suddenly starts into a HDG SEL turn, and then I reconnect the AP and it works. I don't know if this has anything to do with flying exclusively in the VC (I have TH2G triple screens and never fly in 2D). Has anybody else experienced this weird behavior and if so, is there a better fix? My a/c is from JustFlight and has all patches and otherwise seems to work very well in all flight phases. But this HDG SEL anomaly has me perplexed.Thanks for any posts.JS