The transformer in my Headamp KGSS also produces a similar level of hum. Fortunately, it's more than 3 feet away from where I sit.
Getting a KGSS for the price of an SRM-323S is definitely nice, even with the cheap pot and 230V only transformer.
Amazon has the Philips Fidelio X1 on sale for $149.99 (today only):
http://www.amazon.com/dp/B00B3QD94O/?t=slickdeals&tag=slickdeals&ascsubtag=Swv7LoNEEeO73vLLArRDVQ0_ML1w3_0_0_0
The above link does NOT have the Head-Case redirect thing. I think you can use the link provided here and search for the X1 once you get there:
EDIT: It appears to be sold out now.
Since JH13/JH16 without JH3A will also be freqphased, it can't just be a DSP thing. I guess it's a new crossover design that minimizes the phase shifts.
I really like the Redwood parks. Lots of good information about them here:
http://www.redwoodhikes.com/
Bryce Canyon, Zion, Grand Canyon, and Arches are very nice too.