Sony | Sound Connect 4+

This app allows you to configure wireless and noise cancelling headphones in the Sony product portfolio. It is versatile and provides excellent headphone personalisation. I am not aware of anything similar from the headphone competition.
Equaliser: This is the feature I like most. My WH-1000XM2 headphones arrived with a ”default” sound signature. For my ears, they had too much bass and the mid-range vocals were lacking. Using the app equaliser, I managed to optimize these ”deficiencies” and now have the best sounding cans I’ve ever owned. Incredibly clean & detailed mids & treble, plus just enough low end thump (10Hz) to warm up the overall sound without veiling the aforementioned detail.
Why not 5 Stars? There is an annoying uncontrollable ”increasing volume” bug when listening without noise cancelling. I’ve submitted 3 reports to Sony via Apple with lots of information and nothing has improved. Come on Sony!

I have been using Sony WH-1000XM4 with this app and the experience so far wasn't good. Firstly, the UI/UX is not straightforward and badly organized. Labels and submenus especially.
When connecting to multiple devices, the app wont recognize any device, pending with message: "Not connected", even though the headphones are indeed connected and playing music.
It is impossible to switch between both devices on the fly with the app. Instead, one place has to stop playing sound and after 7-10 seconds the target input will switch without any notification. A simple "switching audio input" message would be helpful. Finally, third party app configuration is very limited. Sometimes when using multiple device mode and when connected to smartphone, apps like Duolingo and discord wont work with microphone. This is not a hardware issue and could be relatively easy get patched with an update yet the developers do not prioritize these important issues. For the price I paid for the headphones, I was expecting a rather decent companion app. I hope developers and project managers prioritize some more time on this app and their headphones. Thank you.

Hands down the best set of headphones I’ve ever used. My ears are sensitive and the slightest pressure on the cartilage causes great discomfort after an hour but these xm5’s are super comfy with 5hr sessions not causing the slightest discomfort.
The sound quality is very good with no distortion to higher frequencies during heavy bass output. The inability to fold as small as the xm3 and 4 models I thought would be an inconvenience however the case is relatively flat and compresses when empty.
The noise cancellation function works well, busy airport noise is reduced to the odd shouting voice with tannoy announcements inaudible. In flight noise is reduced to a very minimal hum.
The equalizer adjustment range of frequencies could be greater but then this is across the range of wh-1000 headphones restricted by the Sony connect app