I don't recall how the Q50 works but in my TL, if I set the temperature very low, let's say the lowest, the recirculation is always on. If I set it to a reasonable number, say 72 or 74, the recirculation might start on but then turn off once the cabin is cooled down.
OP, what temperature are you setting your climate control to?
2017 Infiniti Q50 Red Sport 400 RWD, Iridium Blue/Black leather
1999 Nissan Maxima SE, Icelandic Pearl White/Black leather - Supercharged 4AT (322 WHP / 307 WTQ)
2001.5 Audi S4, Santorin Blue Pearl/Black leather - Bi-Turbo 6MT AWD (300+ BHP)
2003 Acura TL Type S, Metallic Gray/Black leather - 5AT - Daily Driver