[ronson]

Glad you managed to figure out the issue and it turned to be an easy fix.

As the others have said, there is no need for a dew cover for the Asiair as it gets warm enough to keep the dew away.

However I would recommend to 'seal' the unused ports, especially the Ethernet port to avoid moisture or dirt build up which could cause issues in the long run. There are dust plugs you can get for Ethernet, USB and other ports from eBay and the likes.