Best sounding and reliable CD changer?

It's the Onkyo DX-C390

I had a Marantz 5 disc changer that I gave to a friend years ago that's still working, as is the one I gave to my son then as well. Reason I gave it away is that I got a music server, which fills the same purpose and is more convenient to use. I think that, or a similar computer audio piece, would be the better way to go, as Peter suggested above.

I still have a Harmon Kardon HK8350 and a Marantz VC5200, which is a DVD/CD changer. The HK is CD only. Both are 5-disc changers.

Both of these are very nice and sound amazing good, but even better through an outboard DAC.

Excellent build quality and have lasted a very long time.

This may be too budget for you but from direct experience I can vouch for this Sony player.

Sony SCD-CE595 5-Disc CD/Super Audio CD Player

I used this CD/SACD player to break-in all sorts of cables and equipment. I would put in 5 different break-in or test CDs and have it play for days/weeks on end. It never had any problems.

When I wasn't using it as a break-in tool and just listened to music is was very nice. No harsh treble and a bit laid back overall.

I've read the Adcom multi-disc changers from yesteryear were also very good. I don't know of any current multi-disc changers though.

I run three Sony 355 units, each with 300 discs. They are chained together. All have optical output. All were purchased as refub's directly from Sony. Running them for almost four years now and no problems. I also have a Sony 595, five disc unit, which I use for SACD's. That also has been highly reliable, going on seven years now. The sound? Almost as good as my Sony 777, which I use in my main system. The changers are used in my office system. Even given I am an IT professional, it never made any sense to me to put my media on a computer, too time consuming, not a meaningful difference in sound quality. I do rip music to my mobile player.