I went out this morning to take flats for last night's shoot, and I couldn't. I'm using the ASI 2600MC Pro. When initiating the Flats using Autorun, it briefly says "Shooting", then "Calculating Exposure" for 40-50 seconds, then terminates. I've used a T-shirt, I've used a light pad, I've adjusted gain. No difference. What might I be missing? Thanks.