Yes, it is deeper issue.. 7.6.1 is not great on the earlier hardware..
Most people who ask about it find that flashing firmware back to 7.5.2 will fix it without causing any issues.. Simply hold the option key when you select firmware update.. and turn off the weekly check for firmware upgrades.. although it will still occasionally flash amber asking to update to the latest worstest firmware.
And it is good you are taking it seriously.. the hdd will be ruined with continuous spin up and down and particularly parking of heads which some of the green drives are renowned for.. they blow up in fairly short order after that.
Thank you so much for your suggestion. I have already flashed my 3rd gen TC back to 7.5.2 and I believe the problem is gone. That said, would you suggest flashing my 4th gen back to 7.5.2 even though it doesn't seem to be exhibiting this behavior? Most likely they will both be used in bridge mode.
Thanks so much!
Later Gen 4 cannot be flashed back to 7.5.x firmware.. the first production run did come out and they still work.. but apple changed the later ones.. simply cannot be flashed back.
For early OS up to SL I recommend sticking with 7.5 firmware but later ones it depends.. apple added a few functions like the btmm via icloud.. although if your TC is older one.. even if gen 4 and can be flashed back.. if it is bridged it won't hurt being back at 7.5.2.
Well I must have an earlier Gen4 model as I was able to flash it back to 7.5.2 as well. So both of my TC's are now running 7.5.2. That said, it's a real shame that Apple hasn't acknowledged this issue and addressed it, as we're now forced with the decision to run an older firmware and lack certain features to gain reliability and proper operation of our Time Capsule's...
Thank you so much for your help!