Receiver power issues help needed

I bought a Kenwood receiver 6.1 w/ 900 total watts for about $200. I have 3 pairs of speakers in separate rooms all wired back to a speaker selector switch, which is wired into my receiver. When I activate all 3 speakers at the same time and turn up the volume to a decent level, the receiver clicks and shuts off. Even selecting just one pair of speakers and turning up the volume results in the same. I'm assuming I need more power of some type in a receiver but don't have a lot of knowledge in this subject. Can anyone help explain what is happening, and what I need to look for in a receiver to fix this problem? Thanks.

That's what you need, and not all are. Receivers don't realy like driving too many speakers simultaneously. If you're very lucky they, shut down and turn on again. Many times they only accomplish half of that.

No offense, but that's not one of the more powerful or duable receivers on the market. It can easily run out of power, even on one set of speakers. By using more than one set of speakers, you increase the possibility of tripping it's protective circuitry, or worse...

The speaker switch might be defective. It might not be keeping the impedance at 8 ohms through all three pairs. On the same token, disconnect the speaker switch and run your main speakers on the receiver main speaker terminals and see if it cuts off then. If it does not, the speaker switch is defective or your receiver is "allergic" to outside speaker switches.