To me, this is less of a logic argument (ie, they should because they are the mfr OR they souldn't because you bought it from an online dealer, etc, etc, etc) than it is a business decision-there are lots of products that have crappy mfr support, but because they sell like hotcakes, the mfr can afford to ignore the impacts (at least on a short term basis) without impacting their bottom line. However, Paradigm does not exactly have a lock on the high end speaker market-in fact, they have A LOT of competition for a relatively small market, which will eventually be the factor that forces them to deal with their apparent low quality customer support problems. No business is altruistic (ie, providing CS because it is the right thing to do) or clueless (ie, ignoring the long term impacts of short sighted decisions) for very long-that is the beauty and the curse of a free marketplace. This sounds like a classic case of the bean counters having too much say in the CS arena-they are probably looking only at the cost of the CS and warranty claims and not the long term impacts of their decisions on future sales.
BTW, you may want to contact your attorney general's office in your state and get guidance on implied warranties-I'm pretty sure that in California, there is a minimum set of requirements for all product warranties that overrides the legalese on the warranty card and requires the manufacturer to stand behind their products at some reasonable level (which definitely applies here, IMHO). Armed with that info, a letter pointing out the legal requirements and their disconnects with those requirements might get you some action (assuming that you have exhausted all other possibilities). Before you do that, you should escalate this issue as high as possible-the higher you go, the more likely you will find someone that does understand the negative impacts of jerking around existing customers and is willing to do something about it.
As for me, I use my feet and my wallet to convey the message to companies that don't provide products or services to my satisfaction, and I would recommend that you do the same.