We have a job where we replaced an amplifier for a client and added a pair of speakers. The original system had a Niles SSVC6 speaker selector, a 100 watt Pararsound amp and 4 pairs of speakers. The new amp is a Parasound 250 watt model and we added one more pair of rock speakers (8 ohm load with new speakers). When we fired everything up, we started getting a knocking speaker selector and all of the speakers sounded distorted. The speaker selector is on its max setting (5/6 pairs).

Niles thinks that the speaker selector is seeing impedance above 8 ohms. We'll be testing that today as all of this happened late at night and we had to beat it but any ideas? The speaker selector is rated at 100 RMS so I think we may be overpowering it. Aside from a bad speaker selector (it worked fine with 4 pairs and the 100 watt amp for 15 years and started having the issue once we put in the new speakers and amp), any ideas?

Thanks in advance