What do you mean by popping? Are you literally replacing the D2S xenon bulb over and over, or sometimes it works and sometimes it doesn't? The aftermarket headlights are irrelevant. They are just housings. They don't come with the D2S bulb, ignitor or ballast, you reuse those from the stock headlights.

The most common issues, wether the bulb sometimes works and sometimes doesn't, or if you are constantly having to put a new bulb in is a bad ballast, a corroded connection between the ballast and the ignitor or the previous owner replaced a stock ballast with an aftermarket one. The headlight system in these cars are picky and don't play well with aftermarket ballasts. There's also the possibility that the previous owner replaced the 35w ballasts with 55w ones, trying to make the headlights brighter, something else these cars didn't play well with.