My 2013 vintage Roamio (model TCD846500) will no longer completely boot up. The behavior has been getting progressively worse for about 2 months with unexplained "Welcome...starting up!" notifications from the unit every few days, until last week when it ceased to startup for the first time. I read many posts and tried many things...nothing has worked thus far. The power-up behavior is this: 1) Green circle light up front comes on. 2) Internal green light is on for 2-3 minutes. 3) Screen says "Welcome...starting up!" 4) The yellow circle light up front flickers for 10-15 seconds. 5) After 2-3 minutes of 1-4 cycle the internal blue light flickers, the TV reports no signal, TV goes dark, then the process repeats. I've allowed this to repeat through as many as 20 cycles...30-40 minutes. No change. I swapped in a properly-rated, working alternate power brick. No change. I replaced the internal hard drive with a clean SATA drive. The new drive did not appear to get initialized. No change. I removed the cable card and restarted. No change. I moved the unit to a different TV and cable. No change. I also connected the original hard drive to my Mac with a USB interface; the drive starts up and reports the correct size, but I can't mount it or see the contents. I do have an option to re-initialize (and presumably reformat) it but I don't want to lose my recordings if they might be recoverable. I now have a new leased TiVo box from my cable provider so I'll be using that going forward. I'm just looking for advice to try and restore my old recordings and repair, re-purpose, or just recycle all or part of my old Roamio. Thanks in advance.