I sent them an email a few days ago, as well. Here was their response.
Hi Mike,
I appreciate you taking the time to bring this to our attention. We've taken a look at this review this week, and are in contact with the manufacturer for guidance. Below is a short response from Kurt:
I was very surprised by the review -- I've had one of these units in my own system for years and have had no problems with it at all. After reading the review I did a series of listening tests with mine, taking the regular speakers out of the system and just feeding the subwoofer, quick-swapping from a direct cable connection to a connection through the transformer. I could hear no difference at all. I then tried this with another subwoofer and, likewise, found no difference at all.
I've written to the transformer company that makes these for us to see if they have any insight. I'm unclear on what the testing setup precisely was, what kind of load was placed on the output, et cetera, so I'm not sure whether the testing was representative of actual use conditions or not. I'll follow up by listen-testing a variety of these drawn from our current inventory, in case there is some difference in quality between batches. There's always the possibility, of course, of a bad unit, but when we've had that arise in the past it's generally been something more like an intermittent connection at one of the RCA jacks. If listening tests fail to reveal anything of interest, I'll follow up with some people I know who can do more in the way of analytical testing.
Right now I don't think we're in a position to tell anyone anything definitive, in large part because I'm not sure anything is actually wrong. I know the product has been very well received and that it is mostly used in home theater systems for subwoofers that are primarily relied on for low-frequency effects. Certainly if anyone asked me what he should use for a high-end audio system, my first reaction would be that you want to try to resolve grounding issues first and foremost, because there will always be some degradation with even the best isolation transformer. Failing that, I'd probably recommend going to Jensen, who make a top-quality product. But I have found this unit great for my own home theater and cannot, even with careful listening and rapid switching between transformer-in and transformer-out condition, hear any impact. We'll see what the transformer people say about it, and go from there.
Kurt,
Blue Jeans Cable