You know what's weird? This just happened to me the other day! I have an N810. Canola2 was working fine for years, and then all of a sudden one day about a week ago, it stopped detecting my removable card. I thought it was just me, but interesting to see that you guys with N900s are having the same issue.

Soooo, I got around this by creating a softlink in /home/user that pointed to my music folder on my external card. From Canola2, I just told it to find my music via this softlink. Maybe you guys can do the reverse and create a softlink from your card back to your phone memory?

I wonder what is causing this?