XP32 or XP64?
don't know if the dual is having an effect, but don't think so
you should have only one at the most showing in the taskbar (system tray?) - I've never had any showing myself - neither taskbar nor systray - been using ODock freeloader for yrs on XP32
2 options to try:
1) clear the cache
http://corkyo.wincustomize.com/articles.aspx?SID=5463&aid=82461&UID=1133455
this will clear all personalized setting and put ODock back to default
2) wipe out ODock and try again
https://www.stardock.com/files/odnt_zapper.exe
download and run this and it will erase all traces of ObjectDock (don't worry it's not automatic... a window pops up and you have to select that which you want gone) - might even want to run a cleaner such a CCleaner - then reboot before reinstalling - might even try a new download incase something caused something to bork on the one you had causing the multiples
If you use The Zapper, you might want to move any downloaded backgrounds, icons, etc to someplace if you want to keep them