After struggling for hours and reading all these postings...here's what finally worked for me. BTW, I'm using a SanDisk 512mb SD memory card.
1) Take the batteries out of your LYRA (I think there's a trick here r.e. the power required for these SD cards to work correctly) 2) With the SD Card inserted, plug your USB cable to it and to your PC 3) You should see it show on your directory listing as an E: External device 4) Now pop the SD disk out of it's slot...wait a second...and then re-insert it. 5) Select the E: drive and choose File > Format > FAT > and don't choose Quick Formatting ....and proceed to Format the SD 6) After it is finished...you should now be able to drag and drop any MP3s to this card 7) Unplug your USB cable...reinstall batteries....and listen away