I always say tray, as that pronunciation was taught me by my late and much-lamented maternal grandmother, of sainted memory. She also taught me the difference between "can I" and "may I", and lectured me on the poor quality of The Stones' later albums when measured against their earlier works. The "tray" thing started as an affectation, and became a totally unaffected habit, that also reminds me of my Nana every time I use it.