I have recently had a lot of problems with my PMDG products (737-800/900 + 777-200LR).
My TCAS starts indicating random planes on my display, even though there is nobody. This can go from a single aircraft, to a swarm of 10. This is specially annoying during a short final, in an already crowded airport (so when I get a warning "CAUTION TRAFFIC", I can't know if it's an actual aircraft or not). To my experience, it only happens in TA/RA and TA only
Until now, I would just turn off the transponder, but this is not a solution I would like to continue using.
Thank you, Martijn