I've used Columbia RCAs for the past three years or so and never had to change the batteries; I do check them occasionally. There is nothing you need to do to turn the DBS "on"; if the batteries aren't dead, it's working.
Audioquest DBS System
I have been thinking about trying out some of the Audioquest Columbia xlrs for my CD player. To those you have the Dbs system in your cables- How long do the batteries last, and when or if they die do you have to buy a whole new battery Pack? if so how much is the replacement packs? Thanks