combining 2 rca cables on 1 source?

So I've got a bluetooth handsfree device that has an internal speaker as well as audio out jack for interconnects. I'm afraid the internal speaker will not be adequate, and what I'd like to do is hook up my front speakers to the audio out feature, but I'm unsure which is the best method to do so without introducing unwanted noise to the system. I've thought of a few solutions, but which is the best? 1) Use a "y" connector and plug both the bluetooth output and radio preout into the "front" input of the 4 channel amplifier without otherwise isolated the cables (radio preouts will be cutoff during calls with the audio interrupt wire from the bluetooth device). 2) Try to find an interconnect relay that triggers with the audio interrupt output from the bluetooth unit to actively switch the interconnects when a call is made or received. 3) Use two amps, the 4 channel for the radio and a 2 channel with the bluetooth output, and use 4 relays to switch the 4 front speaker wires when a call is made or received. 4) Leave the front speakers out of the system, and find a place for a dedicated bluetooth speaker and amp (I have a 2 channel amp sitting around that I could use for this, but I'd have to find a small speaker and place to mount it). 5) other ideas??? I'm putting a good amount of time and using decent amps and speakers for the radio (alpine dva-7996 radio, alpine mrv-f450 amp, alpine type R speakers), and I'd hate to corrupt all the effort and quality put into the system by rigging up some crummy setup just to get bluetooth on the front speakers, but if this can be done with ease I'd prefer it.

I can answer the #2 scenario. I have an older Nakamichi dual RCA level automatic source switch... Lemme know if you wanna make a deal.It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."