Hey everyone I've recently been having some issues with my headlights. I have a 2005 Volvo S40 2.4i that came stock with Xenon lights. Question number one.... I've had to replace my headlights 2 times in the past 3 years, am I buying the wrong bulbs? I dont know if theres a difference between Bi xenon and HID lights and when the stock ones went out I switched them with D2S bulbs from (Meng motorsports). Anyway the first time they went out I put in D2S bulbs and they worked great, no conversion kit needed. I just swapped bulbs and it was golden. 2 years went by and the bulb exploded again so I changed them with the same bulbs as the first time. They worked fine for about a year and just recently I've be driving and my lights or just one light will flicker and shut off. All I would have to do to fix it is turn the lights to the off position and then back on and they worked fine for about 10 to 20 more minutes. Even more recently however its been getting worse. The trick of shutting them off and back on only works for a minute or two before it fails again. I've tried to disassemble the light and shake wires looking for a looking for a loose connection but to no prevail. One thing I noticed is a weird humming sound that is interrupted when that fail. If anyone has any knowledge on what the cause is I would really appreciate it. Whether its the ignitors, the ballasts or the bulbs Id love some help!