Once a system is thoughtfully put together, dialed in, used for a length of time and sounds good for what it is - no.
Aside from tubes/styli I have not made any changes to my main setup in over a decade (I like it as is).
I recently (5+ weeks ago) put together a mini system to listen to CD’s while at the computer.
As the new setup was made from both new and old electronics/speakers/cables (didn’t sound too hot for the first couple of weeks) I "am" listening for changes in the SQ.
Two new/unfamiliar to me parts of the new setup are a Tripp-lite surge protector and Canare 4S11 speaker cable.
If I’m not satisfied with the sound after six months, or so, I will probably start by replacing the Canare with some of the 47 Labs OTA cable that I have been using in two other systems for the past 15-20 years (I have @ least 100’ left), or maybe try some Neotech 22 gauge solid core copper hookup wire (save the OTA for a rainy day).
If that doesn’t do it I’ll borrow a power conditioner/surge protector from the main rig.
I’ve been using a pretty much the same mini system in the living room for 15 years (duplicate Sharp SD-EX111/Polk RT15i speakers) so have an idea of how it should sound.
http://www.laaudiofile.com/sdex111.html
DeKay