The original table has data in it and still has, that was one of the first things I checked once I had tracked down what was happening.
I've tried all the basic stuff and can not find any reason for this, technically its impossible.
Backed up and restored a number of times both manually and running his processes.
Data is in the table at the time of the backup and In Theory should be in the restore but for some unknown reason its not.
The automated processes that run this were not changed and it suddenly started a couple of days ago, no errors or anything to let me know what happened.
As I said its a real head scratcher.
Check to see how many actual backup sets there are in the file. You might be restoring from an earlier set in the same file. Check your backup code/GUI selection to see if you're appending to the media or not. If you are, that could certainly be the problem.