Can someone please explain the Promedia versions and differences? I purchased my Promedia 4.1 back when they were first available directly from Klipsch. Are these old ones the 4.1 version and, other than no headphone jack, how do they differ from V2-400. Can a V2-400 control pod be used on the 4.1 version? And lastly, which version works with the CP-1 (or does both version work with it)? Thanks for any info.