No GUID, no record in feeds_item

Feeds SQL only works for me if GUID is 'not unique'.
If I set as unique, only 1 record is crteated, but all others are 'updated.
The feeds_item table alos only shows 1 record with 1 hash, but no GUID.
When I reverted to using CSV, all items were in this table and all with a guid value as expected.
I would rather use this module so I can use SQL directly.
Please help - thanks.