Do you know for sure that the burners are fouled? You can use a borescope to visually confirm this condition. Are you performing a purge of the fuel lines and system between starts. Did the blow out occur during tuning/test or normal operations? Additionally, it is very common for turbine...
What model-series turbine are you operating? What is the DLN series? DO you moitor combustor dynamics? when was the last mechanicaloutage and what repairs were made?