there is a test button on the DBS housing. I beleive the batteries are user replacable.
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