I saw an old ticket on here closed out pertaining to the issue in the title. My quad is only a few months old and more and more issues keep arising, but the most recent being no tuners available. It acts as if it’s a single tuner. Mine has the internal 1TB hard drive. I have powered it down, blue button reset it, check settings and no luck. Any and all suggestions will be welcomed.
You’ve got a 12 month warranty so I’d contact Tablo, if the tuners are failing/failed you can get a replacement.