try the 4 ohm tap.
Absolutely agree, as this has been discussed numerous times in many threads. The 8 ohms of a speaker is the nominal rating, however it varies as the speaker plays due to different frequencies. I have read that many Paradigm speakers will drop significantly from the 8 ohm nominal rating as it plays, and one member found that his Paradigm speakers had a better overall balance using the 4 ohm tap instead of the 8 ohm tap. This will not cause any problem whatsoever, or result in any damage to amp or speakers. Doing the opposite, that is, using a speaker with a nominal 4 ohm rating on the 8 ohm tap is not recommended, as this could result in a problem to the amp. Again, I highly recommend trying the 4 ohm tap with your 8 ohm Paradigm speakers. Here is a quote by Bifwynne, the member with the 8 ohm nominal Paradigm speakers, in one of the threads I mentioned,
Bass is clearly more extended and tighter. No surprise there since the output impedance off the 4 ohm taps is less than the 8 ohm taps (therefore higher DF). Plus, speaker impedance in the "power zone" (say 60 Hz to 700 Hz) is for the most part 4 to 5 ohms), ergo a better impedance match for the amp where it is being called upon to deliver most of its juice. Imaging was less forward (probably because midrange/treble was less emphasized as a result of higher impedance), so I turned up the gain and imaging came back. In short the rig plays louder, but not as harsh (i.e., maybe less distortion).