I think you misunderstood what I meant by "a reference to the Rolling Stones." I was saying that Van Halen was referencing the Stones by using brown M&Ms as their test.
I remember from the late 60s/early 70s hearing that the Stones actually asked for a bowl of all brown M&Ms in their dressing room. Not as a test but because Richards, as I recall, just liked brown M&Ms. Could be Van Halen heard the same thing and used it as their test clause as a nod to the Stones. I did try to verify that but can't find anything - it was a long time ago.