Second Play:5 to create stereo pair - the original speaker keeps failing

I wrote this in "Ask A Question" 2 days ago and I can't find it anywhere. I just bought a second Play:5 to create a stereo pair. I also have a bridge dock which I got with the first Play:5. The stereo pair keeps losing the right (original) speaker at seemingly random times. In my iPod app they are listed as "Living Room (L+?)" when it goes wrong. I have to separate the pair and add the missing speaker as a new component again. The R speaker seems to come and go when it pleases. Its very annoying! Not sure how long I can put up with it.