The mysterious problem of the fast clock on the Mac Pro rev2

According to readers in the Forums , some Mac Pro's are experiencing a strange problem. Their internal clock is too fast, time is shifting ahead about 5 minutes per hour.
This might not sound dramatic, but it is worrying since it disrupts the date-of-creation of files and certainly the storage backups of Time Machine.
Currently Apple has not commented on this issue. But knowing that the Mac Pro clock is on the motherboard, it will take at best an updated EFI and at worst a change of the latter to overcome the problem.