Yes, some Arc users have complained about the Arc being to “harsh” sounding. I think it may just be a combination of the Arc’s sound profile, personal preference, and the sound profile you are used to hearing from your Samsung sound bar.

Have you tried performing Trueplay tuning with a different model iOS device? What model TV do you have?

Thanks for reply. 
I have an LG 55C2. Ive not tried a different phone, mine is an iPhone 13 running 16.3.

I think you’re right it might just be my personal preference, I really don’t like a harsh sound. Pity, as it sounds great with Dolby Atmos but the standard PCM 2.0 which bbc1, itv etc seem to broadcast in cones across (to my ears) as very sibilant, annoyingly so. Do you know if the Beam has a less harsh sound?

thanks. 
 

I’m not sure if the Beam is less harsh sounding, but I have seen far less complaints about the Beam than the Arc.

I really do recommend trying Trueplay with a different iOS device. Different model devices can give you different results. I would also try turning off the Loudness setting in the Sonos app and adjusting the treble lower in the EQ settings.

If you haven’t already done so, set the TV to these settings:

HDMI Input Audio Format: Bitstream

Digital Sound Output: Pass Through

eARC Support: On

I’ve got Beam(1 and 2) and am hypersensitive to sibilance - as my wife can attest 2 LG TVs have been returned in the past because of this. ! But the beam seems, to me, to be fine. Not compared it to Arc, but it might be worth exploring.

Thanks all for your replies, appreciated. 
Ive changed my tv settings to pass through and I think that might have helped - thank you.

im still in my 90 days period from Sonos so I’ll keep persevering, and if no joy I’ll try the Beam. 
 

I need to find a solution somehow as my far less discerning wife is being driven mad by my constant tinkering with settings!