Gareth, apologies if I've turned you against the 800. Yes, I am critical of it because of its price, but the modified unit here still is THE best sounding CDP. However the law of diminishing returns sets in with a vengence at this level but I would guess that going for a Linn is not going to give you what you want.
Maybe I've missed some of your earlier postings but are you mating it to a Meridian 861? If so I suggest you look for upgrades further down the chain if you are reluctant to have the 800 modified with a better timing clock etc.
The musical sound you are hearing is the result of a system, and the room is a vital component of that. Many unjustly criticise speakers because the sound comes from them but do not get too obsessed with the primary source either. Both are important as are all links in the chain.
The danger with this audio obsession (and I have suffered it too) is to lose sight (and sound) of the music and instead listen for perceived faults in the reproduction. For sure bad amplifiers etc can detract from musical appreciation but we have all enjoyed music on boom boxes at times, although these are obviously not a long term choice. Yesterday I was listening to a Cetra mono reissue on a Warner Fonit CD and was blown away by how great this 1954-1956 recording sounded, especially in the light of how unlistenable I had found Cetra to be on vinyl previously.
So. a few suggestions:
1. Take a few days break from your system and then come back to it listening to a CD you enjoy.
2. If you are still unhappy with the sound (meaning you cannot enjoy the music) then try different non CD sources to double check the "problems" you hear are not in the amplifiers or speakers.
3. If you are convinced the rest of the audio chain is fine then investigate upgrading the 800 (effectively turning it into an 808), but do not waste money on a Linn.
Hope this helps. I empathise how miserable it can make you feel if you are convinced you made an error of judgement in your 800 purchase. Be reassured it is a SOA component and I would never advise anyone who has one to sell it. What I do advise is that there are much more economical ways of getting into SOA 2 CH or DVD.
Please tell us the end result of your anguish.
John