Problem with scenery loading / 737 night panel

Hey guys!!!I don't know if you have seen this issue before.It happens to me anytime I am flying the 737NG at night. Whenever FS2004 does a "Loading scenery" at night, when it comes back to the 737NG panel, the AP numbers are gone and the switches and gauges are all messed up.It happens all the time and only when flying at night.I have a:P4, 2.4GHz, 1GB RAM, 128MB Nvidia video card, 80GB HDD, CH Virtual Pilot, CH Throttle quadrant and Pedals.Installed in FS2004 I have Activesky 2004, PMDG, LevelD, and some other aircrafts. The problem only happens with the PMDG aircraft at night. The redundant heading indicator, altimeter and other gauges are blank. Very weird phenomenon.Any suggestions?I tried reinstalling FS2004 and did no difference.Teo