Barbarian turn lag

[titileterrible]

When I play on a giant map (like "Leargest Earth") of YnAMP mod, when i encountered a barbarian unit, the duration of AI's turn increase from 5 / 10 seconds to 4 / 5 minutes... And just after discovery of a technology or a civic, the AI's turn come back to a normal duration.

I tried with all options combinations of Quick Combat, Quick Movement and auto End Turn : Same issue !

Any idea ?