We need Audiophile Edition version of Port

Yup, and I wish Sonos positioned Port just like an Amp but without the amp. But they didn’t!  Oh well.

So does the Port, via UPnP or any of the dozens of Sonos-supported services, including your own music on a NAS...

To feed what downstream equipment? Over what type of connection? 

Dac/preamp that can do crossover and room EQ in the digital domain like a MiniDSP SHD.  Then feed a power amp, speakers, and subs.

Port can already do that, but having a digital input and rudimentary home theater decode (like the AMP) would let me feed my TV to it and not have to mess with a big AVR at all.  If I swapped for a Port + preamp setup, I lose the ability to add 2 Ones for surround sound.

Not a big deal and I’m sure I’m a corner case.

I haven't read the link, so bear with me - are these issues OTHER than ones relating to unstable wireless music play of dense HD streams?

I would love an audiophile port as Sonos ease of use is excellent and I believed all the claims on here that Sonos could deliver quality digital output. Unfortunately Sonos as hifi components consistently get a poor reviews for a reason as I recently found out. Replacing Sonos with another digital source has made a night and day difference to my hifi. A great lifestyle product but severely restricts the sound quality on good hifi to the extent the sound is so distorted it was physically painful to listen to. Replacing Sonos with a far cheaper option of a USB cable has solved the problem and greatly increased my listening pleasure.

I still wish that Sonos will bring out a quality hifi source as I’m a Sonos fan but I’m not holding my breath as while I’m sure they have the technical capability it is just not  their market which is fair enough. 

Uh-huh. 

I would say really enjoying my hifi headphones because they sounded so clear revealing and natural and wanting to listen to them every day after switching to an alternative source is a night and day difference.

Switching from variable to fixed volume as recommended on here certainly removed a lot of the Sonos distortion but still on Sonos I could only listen to my headphones for a short period as they hurt my ears.
 

My headphones really started to sing and become really enjoyable and made me realise why they had such a good reputation when I switched from Sonos. With Sonos they were disappointing and unpleasant to listen to. I would say that is a night and day difference. 
 

I have 8 Sonos units as I think they are an excellent life style product but they are not hifi and simply not suitable for a revealing pair of headphones. Just as previously my previous amp was simply not powerful or good enough to drive them.  
 

Some people seem to believe that Sonos is way better than other music systems  but that there is nothing better.  For a lot of people that may well be true and Sonos is a lot better than basic systems. but personally I get a lot more pleasure from a less processed sound which is more natural. I’ve no doubt that doesn’t do anything for a lot of people but for some it does. It is merely  personal preference and what people are willing and able to pay. Clearly Sonos get that right for a lot of people as it is a mass market product but it is not hifi which is fine as it doesn’t claim to be.

But there are a lot better and cheaper or similar priced options as I found out when I listened to my ears rather than people who refuse to accept that there could be hifi sources that sound better than Sonos. Personally I don’t believe that there are other systems that sound better than mine. Whether they are worth it is another personal question. 

You have set yourself up for a similar challenge after someone else discovers that their system sounds better than yours.

Sorry that was not clear or what I meant to say.  I strongly suspect that there are other headphone systems that sound better or different to mine and they may also well be cheaper. I got a special offer and could not test due to lockdown.  They are a lot better than my other headphones/earbuds though but was underwhelmed until I switched from Sonos to a USB cable. 
 

I’ve tested lots of different earbuds and dac options though and they all sound very different and either really enjoyed or didn’t. The earbud I most enjoyed was not a hifi brand and not the most expensive hence why I think different music systems sound different and the most expensive is not necessarily the best. I don’t enjoy Sonos as a hifi souce. I do enjoy the sound from the cheaper USB cable option. . That is a night and day difference for me personally. 
 

im just saying diffferent systems sound very different to me and that Sonos as good as it is is not the be all and end all system for everyone for every situation. Different people just have different preferences.