Unexpected clef change at beginning of system.

I begin my score with bassoons in tenor clef and C horns in treble. I select the appropriate bars and double click on the desired clef. Save and close. Re-open and the original default clefs return (bass for horn and bassoons) with the clefs I set now as courtesy clefs after the time signature. Is there a cure for this? The attached images show before and after reopening the score.

This is ms 3.0.5