What phone did you use to TunePlay prior to the update?, it could just be your experience moving to an iPhone 7 rather than the update itself. (7 TunePlay performed significantly better than the X/Xs prior to the update in my experience, there is a clear issue with X/Xs which is immediately noticeable).

Same here! No noticeable difference

I got my hands on an iPhone 7 this morning. I downloaded the Sonos S2 app and Trueplayed my room. 
 

The sound was definitely improved. It’s like the Arc took a step forward in presence. I use to describe its sound as “small.” Now not so much. It’s still silly bright but I’m not experiencing ear fatigue. 
 

Of course I hear they released an update and to my surprise, I had the updated app on the iPhone 7. So I’m not sure if they changed something or if the tune from the iPhone 7 is helping things. 
 

I’m very aware of the power of the brain, so I like to keep things flat (eq, loudness, sub off) as I’m evaluating the sound. I believe something has improved though I’m not sure if it’s the tune from an iPhone 7 or the update. 
 

I’m going to swap in the Beam for further reference. 

Upon the first trueplay attempt post update, the sonos app crashed after the “sit where you watch” phase of trueplay. I reran trueplay and it went through fine. In my experience, sound seems somewhat better, but still brighter than I would like.  
I look forward to further fixes and tweaks by Sonos. 

No change for me!!!!!!!Still harsh!!!!

Fingers crossed this helps. I have just installed the update and true played again. The trueplay felt like it took longer (I got to go around the room twice). Maybe they have updated that. Jury is out on whether it’s altered the sound profile...

Lets hope someone who is experiencing the ‘bright’ sound with their Arc can update their App, do another Trueplay and report back.

No clue cause yet again Sonos has not provided any info...

Trueplay Update ?

No System Update though. On top of that in About My System says Version 12.0.2 but at the bottom under Sonos System Info still says 12.0.1

12.0.2 just came out, installing now

Hey Sonos! Can we get something more than a generic response? It’s your flagship product we are talking about. If you have forgotten- we are end consumers, not beta testers. So, fix your issues as soon as possible.

I also turned with iPhone 7 and feel vocal’s are still way too harsh, definitely better than iPhone X tuning which is unbearable, but still very high pitched. This needs to be fixed ASAP. 
 

it feels like dialogue completely takes over the overall sound and just way too “in your face”, even with dialoge enhancement and loudness turned off.

I just want to add that my initial true play attempts with iPhone Xs resulted in the harsh metallic unbearable sound signature. Even reducing treble didn’t help. When the Bass fix update arrived, I added sub and did Trueplay with iPhone 7. I am happy to report that the metallic sounds have all gone and my treble is back to 0. There is definitely something going on with the mic filters and how sonos is processing the Trueplay with different gains. Its been about 10 days and countless listening sessions and I am satisfied with the way its sounding for music and movies. It think its a Software issue and Sonos really need to test it with multiple iOS devices to see how the sound signature differs and compensate for the differences in Trueplay tuning.

There are 2 steps, the first you hold the phone where you sit watching the TV, stationary, I think this is for the surround calculation.

The second step, I think for EQ,  Sonos App asks you to walk around the room waving the phone. I didn’t do this to get best results for me. I just waved the phone a foot above and below ear height along the sofa, back again, and repeat. I was keeping the phone moving slowly, but in a concentrated space, ie where your ears are most of the time. The iPhone speaker needs to hear the high frequencies, if it has a cover and/or there is dust/pocket fluff in Mic, it will affect Trueplay.

Carpet will help :)

So you did not move at all? You did all the tuning on 1 spot?

Interresting, I also have a large livingroom (L-shaped) with hard flooring, getting a carpet in the living area this week.. 

I might try the Arc in my bedroom (small, carpet, curtains) to see if there is a difference. Of course this is no solution. The Arc is designed for large livingrooms, the Beam for small/medium. But it might lead to some explenation/insight. With a possible solution: better truplay tuning in large rooms?

Can you try another Trueplay? I got best results just waving up and down along the sofa, rather than waving around whole room, make sure you remove iPhone cover and check mic for dust/fluff:

https://en.community.sonos.com/home-theater-228993/optimum-trueplay-6842990

Fairly large living room. Square layout. Flooring not sure (feels like marble or granite).  No curtain or carpet. 

My room setup is not really optimal, but I do expect decent audio quality.

My desktop speaker costing 1/3 of the Arc's price performs better in the same environment.

Izy1987: you're description of the problem is very recognisable. Could you describe you're room? Large open space, hard floor, etc…?

No IFs, a room will definitely make a difference to sound. If you ever walk into an empty unfurnished room, its sounds very different when you walk in again when its carpeted and furnished.

If too much sound is bouncing around it will smear imaging and in many cases cause the overall sound to be bright and fatiguing. The trend amongst speaker manufacturers is to make speakers that are already too bright (to make them sound more "exciting" during sales demos) so in a room with too much sound reflection, these speakers can be extremely irritating. Certain wall surfaces such as glass or drywall which are popular in modern condo style apartments are atrocious when it comes to treble information and in many cases will echo because there are so many reflections. This destroys imaging as well as intelligibility of speech and transients. Drums especially can blur together so badly that you can't hear individual notes anymore. Voices can have terrible "esses".

https://www.planetofsoundonline.com/pages/fixing-your-room-acoustics

If Trueplay is making your setup worse, I would try another Trueplay, and focus on the area you are listening, and if possible try another (older) iDevice.

Thinking about this...its obvious trueplay is broken (new ios devices especcialy), so fixing treuplay could potentially resolve in a less bright sound in these kinds of enviroments…..

IF (and thats a big IF) the room is part of the problem, shouldn't trueplay make it sound better? Now trueplay makes it sound worse...

Have you ever been in a room where the audio, be it music or a movie soundtrack, sounds really “tinny” or “crisp”? It’s what we refer to in the industry as “bright”. Taming bright speakers is a big deal if you want to maintain clarity without achieving a harsh or unruly sound. While a loudspeaker can be responsible for this, it can also be the effects of a room. A room can also “muddy” the sound by creating a reverberant effect that reflects the sound back into itself over and over again. Most rooms aren’t large enough to create an actual echo, but if they are made of concrete, hard surfaces and lots of glass, the effects can be detrimental to your listening enjoyment.

http://www.audiogurus.com/learn/speakers/taming-bright-speakers/902

Meanwhile at Sonos headquarters..” Sh*t, this topic about tiny, harsh treble isn't dying out by itself...what to do? keep silent or not?….”