We mean the songs inside of those custom albums. For example, before IOS18 when I synced the audio files from my Mac, they would appear in alphabetical order on my iPhone and iPad. Here is an example:
A - Song 1
B - Song 2
C - Song 3
D - Song 4
...etc
However, after IOS18, the songs are no longer in alphabetical order. They are randomized. For example, this is what they show up like in IOS 18:
D - Song 4
A- Song 1
C - Song 3
B - Song 2
...etc
They still appear in alphabetical order on Mac (apparently even after updating, but I can't confirm since I don't want to update because it'll probably break something). It's very annoying because instead of looking at the album and finding the song via A-Z, I have to look through all the songs. This is especially annoying from custom albums that have many audio files.
Note: This happens when creating custom albums with custom audio files on Mac. I work with of music exported from LogicPro, so I make custom albums to organize them. Talk about a step down for a 1.7K iPhone and a 2k Mac.