I replied with this on another post in the community, but thought I would post here too so others can see it.
I've been following this issue since the beginning. Thought I would post what's happened to me in case it's happening to others as well.
The update to 14.7 did not work for me on my iPhone 11 Pro Max. Lossless tracks over wifi and cellular still stop at 15 seconds.
However, since converting all of my iTunes purchases over to Apple Music since the announcement to lossless tracks was made on June 6, I've noticed some interesting things:
1) Only my purchased tracks from iTunes that I am streaming in lossless stop after 15 seconds. Does not matter if they are played over wifi or cellular - they stop after 15 seconds. If these same tracks are downloaded they play fine.
2) Any track that I add to my library directly through Apple Music, that was not purchased through iTunes, plays lossless fine over wifi and cellular and with all Atmos options enabled.
3) Since the 14.7 update I've noticed that only my purchased tracks from iTunes with a "release date" from the artist that was AFTER September 1, 2019 stop after 15 seconds when streaming lossless over wifi or cellular. All tracks I purchased from iTunes with a release date prior to September 1, 2019 play fine in lossless.
So, if an album/song was released by the artist to iTunes after September 1, 2019, I have the 15 second issue - even if I bought the album/song in say, January 2020. If the album/song was released by the artist to iTunes prior to September 1, 2019, I do not have the 15 second issue regardless of when I purchased the album/song.
4) Since the 14.7 update when these same tracks I purchased on iTunes after a "release date" of September 1, 2019 are played, I now get an error message when the track stops at 15 seconds that says, "Cannot Decode - The media data could not be decoded. It may be damaged." I did not get this message with 14.6.
5) Since the 14.7 update any track that I add to my library directly through Apple Music, that was not purchased through iTunes, still plays lossless fine over wifi and cellular and with all Atmos options enabled.
6) I am able to play all tracks if lossless is turned off.
7) I am able to play ALL music over lossless with no issues over my MacBook Pro and AppleTV.
And while I do see a lot of posts that say 14.7 fixed the issue, it probably did if your main source of music was streaming/downloading strictly through Apple Music.
However, if you happened to buy your music through iTunes and recently moved to Apple Music in that last few weeks to past 10 months, I encourage you to play those tracks you purchased in that time frame, and have now since uploaded to Apple Music. I bet those tracks still stop after 15 seconds in lossless with 14.7.
Still some work to be done before this is fixed for everyone.
