Hey, I recently picked up a MURF to add to growing collection of Moogerfoogers. I believe it is an older model because it has a 50th Ann. sticker on the side of it. At any rate, I was messing around with alternating between feeding my mixer the mono and stereo output. I was under the impression that with a cable in the mono output only all the filters feed through the mono and with a cable in the right output the filters alternate between the two. to my ears I heard filter steps in stereo that I never heard under the mono condition…what might be the cause of this? Was it because I was using TRS cables rather than phono?
Yes. Stick to TS cables for audio signals, unless you have some other tricks up your sleeve. 
Thanks. Hmm yeah that’s a pain…the only snake that I have right now, which I can use to run from my patchbay to the various audio ins and out to my 'Fooger board is TRS…