disk capacity hours?

I was browsing through the "System Information" area of the DTivo receivers, when I noticed that both my receivers have 9 less hours of disk space capacity, 244 hours to 235 hours and 392 hours to 383 hours, is anybody's disk space also have decreased in hours? is there anyway to get back those 9 hours? thanks for any help



PS-I also notice that when I use the "nuke_deleted.tcl and mkDiskConfigHijack.tcl" scripts the "nuke_deleted.tcl" one works fine but the "mkDiskConfigHijack.tcl" one gives the following error, (No Active DiskConfiguration to deactivate Object modification failed: can't open object (errDBNotFound) Finished.)
could that be the cause of the 9 hours lost?