Manual setting of stagger

Hi guys
If you could help me i would be very grateful
I have plotted multiple 8 tb drives over multiple computers
The problem I am having is when connecting multiple drives in a single computer
I set the starting nonce as the stagger size from last plot plus 1
When i do this i got loads of non confirmed downloads as if the plots are corrupted
If i run a single drive starting from 0-300000000 across multiple plots i dont have a problem
can someone please inform me the manual way of setting this correctly over multiple drives