the Intellipark issue with TiVo HD's is not relevent here, as it only effects soft reboots. Hard reboots are fine even on TiVo HD's without intellipark disabled. It only becomes an issue after a soft reboot from the menus or after a software update.

The problem is a change made by WD to the firmware of some drives starting around Jan 2009 which made them incompatible (even the same model which worked in 2008 did not work if made in 2009), WD had promised to correct the issue by mid 2009 but never did.

I don't know which new "feature" actually causes the issue.

Peter.