I don't have a Hugo but I do have a Mojo.
Here is the simplest solution to keeping the Mojo cooler, and the physics will apply equally well to the Hugo.
http://www.head-fi.org/t/788913/chord-mojo-issue-solutions-thread/270#post_12731782
To maximise the cooling, you need to allow the maximum surface area of the Hugo, to be accessible to a cooling air flow - If you have your Hugo placed flat on your table, then one of the two large flat areas is facing the table top, and not really experiencing any air flow.
I suspect that your problems too are caused by the high summer temperatures.
Try standing your Hugo on one of its sides.
If this solves your problem, it is a lot less hassle that returning your Hugo to Chord.