From everything I have read, the awning slides are designed to do this. The first time I was camped in strong winds my bedroom slide topper would billow but always retract when the wind would subside. If they didn't do that they could rip off. Anyway, if the noise becomes too annoying just pull back in the slide while asleep but I don't think it actually hurts anything. I do agree the squeaking sound of the spring caused by the billowing can make it hard to sleep.
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