When starting up Firefox, most of the time it doesn't start, or starts only when I open firefox for the second or third time. I have checked my system's resources while starting firefox and it appears that it is having issues reading some files.
It is reading a lot (100 or so) of cache files, but can't get it's speed up. These files are read at a maximum of 4096 bytes/s. When I start firefox for a second time, most of the time it instantly stops reading these cache files and I get 2 Firefox windows.
I have the latest version of Firefox installed, without add-ons.