+1 for me too. Great work with the continuing evolution of the aux input solution.
I could try and make it myself, but I'm glad you've already done all the work and saved me unknown hours of time. The only things I would do differently are to use all SMT components to reduce size and cost, and perhaps replace the electromechanical relay with an analog switch for clickless switching. Here are some analog switch chips:
http://www.analog.com/en/switchesmul...cts/index.html
http://www.onsemi.com/PowerSolutions...rics.do?id=968
http://www.fairchildsemi.com/product...dioswitch.html