Data arrived in ODS new data - all data fields are cleared

Hello Experts

We are loading every day since 3 years data into a DSO There is a simple start routine.

Issue:

Suddenly 1x record out of 12'000 records loses the data fields or in other words the data fields are cleared. The key part of the record still extists. The table of new data shows the record with all cleared data fields. Thus before activation the data are lost already somwhere in updating.

We dont use expert routines, no end routines ect. It is a simple 1:1 transformation with a simple start routine.

We debugged the start routine and the record still exists correctly at the end of the start routine with all entries in the data fields.

So quite tricky and we hope of some good ideas , you may help us.

Thanks a lot for your input and help

Christian

Our system is SAP BW 7.01 on DB6