The Disease! 
Well, not quiet as bad as some I know.
I had to replace my Focals after they were killed by the cats.
A friend lent me an old pair of SBLs he had lying around, and they worked soooo well in my room that I bought them.
Having fitted them with the LAST set of SBL drivers that Naim had the left the mid/bass was roasted by an amp I was reviewing …so I had to buy another pair. But they were Mk2, and I now have a collection of spare drivers in the loft.
The LP12/Aro/'Geddon are unchanged for decades. The Troika is newer, and has been refettled twice.
The 534 didn’t work as well with the SBLs as one of my old 250s, and after some listening a 300DR was purchased a few years ago. That won’t be going anywhere.
I loved the EAR868, but really hankered after the 912. BUT, I thought the Townshend Allegri was as good as a line stage, sans the phono and remote. Which led me to the Icon 4 autoformer passive, with remote. An absolute BARGAIN at the time. Gone up a bit since, but still great VFM.
Phono stages were interesting. But the Tron 7 GT solved that and will be staying. Just serviced and upgraded.
Which leads me to DACs.
I am not convinced you achieve a LOT by changing DACs. But, the small differences are important, unfortunately. Would you rather drink a good New World or an 1855 classification bordeaux? Depends on a range of factors.
A part of the equation is how wide open your system is, which itself depends on your room …etc.
Which is better: Ferrum DAC + Hypsos; Weiss 204 + PS102; PS Audio StellarGold DAC; Laiv Harmony; or Mola Mola Tambaqui?
All sound great in my system, with minor differences; which makes cable selection and setup important.
I have settled on the Weiss, and HOPE to just stick 
I confess that I am toying with buying the Nagra Streamer.
I have bought some other gear, but that is to assist with reviewing. Giving a piece of gear a sympathetic system with which to work.
The death of the Oppo was an anticipated blow, but it gave me over a decade of reliable service.
I may well just stick with the small Sony for the moment, and revisit it when the Phillips TV dies.
I have just bought nVidia Shield Pro, curiosity. In my case I have a LOT of old series in lower res formats and would like to see what it can make of them.
M