P4P800 w/ USB Mass storage device issues

I have an Asus P4P800 Deluxe mobo and an internal Mitsumi 7-in-1 Flash Media/Floppy Drive. It has seperate connections for the floppy (floppy cable) and the USB digital media drive (internal USB cable that hooks up directly to the mobo). Now the Floppy part of the drive shows up normally, it's the USB media drive (which shows up as two seperate drives - 1 flashcard drive and 1 SM/MMC/SD drive) that has issues. During POST, it's luck of the draw, it seems, if my mobo detects the digital media drive correctly. It'll say it sees 3 USB devices: 1 mouse, 2 mass storage devices. Then it goes down through all the components and when it tries to decipher exactly what those 2 mass storage devices are, it either does it flawlessly, or it just hangs for about 20 seconds, gives up, and moves on into windows where the drives don't show up. So to sum all that up, sometimes my USB digital media drive (as the two drives) shows up and sometimes it doesn't. So what's up with that? Is there a problem with my mobo or my floppy/media drive? Come to think of it, I didn't have these issues when I only had an IDE harddrive on my system. I started having problems when I installed my new SATA harddrive. Is there a known SATA/USB conflict issue?

<font color=blue>Asus P4P800 Deluxe, 2.6C @ 3.25Ghz, 1GB Geil Platinum PC4000, Radeon 9800 Pro, SB Audigy 2, Antec TrueBlue 480, 2x120GB Maxtor DM+9's: 1 SATA, 1 PATA, Plextor DVD+RW, Plextor CD-RW.</font color=blue>