Maintain Conversion factors for TRY/EUR (Currency Type EURX)

We are facing strange error.

Maintain Conversion factors for TRY/EUR (Currency Type EURX) is a common type of error as see existing SCN posts but strange thing is this error only in case of DELTA load and NOT in case on FULL load in our case.

DELTA DTP to DSO failing - FULL DTP to DSO successful

This suggests that all entries in OBBS and related transactions for Conversion factors are maintained as the data loads in case of FULLL load but why is it failing in Delta is still not clear.

Can anybody suggest on it?

Thanks,

Rahul S