Shanling CD-T80
Copyright 2011 © Troels Gravesen

Vinyl is my main source of music, but I do have a lot of CDs and care about what comes through. I bought this player from Cattylink/Hong Kong and it's been a good workhorse for several years.
Some info can be found on diyAudio on tweaking the CT80 and the only thing I have done is changing the output caps to silver/golds from Jantzen Audio. I haven't tried changing the integrated circuits like suggested from the link. I tried this with quite a few CD players over the years and never really found much improvement.
Visitors have kindly brought in serious expensive CD players, but none has convinced me that a new player was needed; this even goes for a cutting edge 24 bit DAC.
Apparently most tweakers go for the op-amps or the buffer tubes, but no one seems interested in the output capacitors, a bunch of electrolytic caps! This would be my usual suspect and and do believe my current silver/golds outperforms the electrolytic caps.
The 6N3P output tubes most likely never needs changing.

The Jantzen Audio silver/gold caps. Here some prototypes, the current Jantzen Silver/Golds look better.
I use 2.2 uF but you may have to check your line stage input impedance if this is enough.

Unsolder the four electrolytics and connect as seen on photo.

Final caps, 3.9 uF Jantzen Audio Silver/Golds