I was getting fed up with the odd Spotify dropout and my Music Room disc always reporting 'poor connection' with a yellow light so I bit the bullet and placed it directly opposite the house on the inside wall, the absolute closest it can be distance-wise to the Utility Room disc. This entailed putting it half way up the staircase shaft! At last I now get a blue light and 'good connection'. I had a whole evening's listening without a single glitch.

By the way, the BT Whole Home system gets a 'recommended' verdict in this month's PC Pro magazine.

I'm with virmin, been with them for years,had a prob with the for a few years due to over utilisation,so I refused to pay them,sent them load of screen shots of the speed tests it got to a point ,where quite a few people were coming to my house to ask what was going on with the slow speeds 150 mb.so anyway after a few arguments I said if they like I would print off a few hundred posters and attach them to telegraph posts ,street lights and local shops for people to check there speeds and if they low contact virmin,as they will only listen if quite a few punters complain.the problem they had was a major issue with the local ubr was faulty.now that's a big problem for them to sort out.so every month I had to phone up an quote a fault number and they gave me my payment back.they kept on changing the super hubs ,in the end I would not let them in till they fixed the fault on the ubr as they were wasting my time and there's .they also done repulls to see if that would solve the problem,but it wouldn't ,they gave me home plugs to see if that would sort it but that only sent distortions and mains hum through the hifi system especially the turntable moving coil boards.i thought it was a problem in the Naim phono sockets,anyway I change every component on the boards.that did not sort it,so when speaking to my mate he ask if I was using home plugs I said yes ,he said disconnect them,the noise disappeared,well that was sorted,now back to virmin.they eventually sorted out the ubr and now I get just over 300 mpbs so I have to start to pay them again.i refused a super hub 3 as that has it own problems with the chip it uses (dropouts).so now I use the superhub 2 still with a Netgear r7000 vpn installed ipvanish router ,so now I get very oood wifi if I ever use wifi.my house is on the large side so there router was incapable to send long range wifi in my humble aboard ,even wifi home plugs generated a lot of noise through the airwaves and mains cable and I use a separate cable to a second consumer unit.you have to put your foot down with the isp suppliers,I think they have to pay you back upto £7 a day if you are not getting roughly what you are paying for.a good speed test to use is thinkbroad band as there speed test has wich ubr you are on and is back by the government ,it also gives jitter,latency and speed tests also it has some useful settings.i good musician once said power to the people (Wolfe. Citizen smith)lol

My quandary with wi-fi to the music room continues. I cannot get an ethernet cable over there easily - certainly not without raising paving on two levels. The BT Whole Home system just about stretches there but is weather dependent. Sometimes I get a blue good connection, other times a yellow poor one. Most evenings I get undisturbed listening, others I get dropouts making listening impossible. Holding it at 2.4GHz wireless-n helps as 5GHz wireless-ac is useless over that distance.  I thought of resurrecting the phone line used when it was an office, but it would at best be another 20Mbps on FTTC and double the cost.

I've experimented with my mobile data over there, and despite getting only 2 bars on EE I can achieve a consistent 30Mbps speed anywhere in the room. So 4G is better than FTTC for me.

Right then, it's time to try another solution. A TP-Link MR6400 4G router is on its way.  Dedicated to music streaming only, this should get me 30Mbps and will allow me to run the Pi from an ethernet cable.  Got to order a SIM for it tomorrow.

You should look at the BT Whole Home mesh system, Stan. I do recommend it (except for my music room) and it's not too expensive. Four discs cover our rather large barn.

Can I assume that you have the Pi plugged into the LAN socket on one of those BT Mesh discs? And that disc is communicating directly with the BT base unit?
If my assumption is correct, then you are touching on the same kind of issue that I have been fighting with. My place is not that big, but I am living in a wifi hostile environment. I think that I might have finally come up with an idea to tackle the problem. But I am waiting on one key part to arrive for me to put my theory into practice.

What about putting a repeater between the nearest disc to the music room and the music room itself? Or one of those mains network in the power line to the music room?

I've got the 4G router up and running and am getting 36Mbps in the music room (compared with barely 20Mbps from Infinity over a dodgy wi-fi link). The Pi is connected via ethernet cable and I swear it sounds even better now.

That's a result.

It's just... punchier over ethernet cable compared with wi-fi, John.

I've turned wi-fi off in Volumio, which I think helps.

I think with where you are in your set up and sound it is worth optimising everything to the max.