• Many ogg audio files were modified so music loops can now play and repeat seamlessly, with the instruments finally synced. Loops also start playing at the beginning in most cases now.
  
  
• I got rid of many audio gaps in the ogg files, and made sure to avoid getting high pitched clicking sound artifacts the moment a loop repeats due to a bad cut in the audio spectrum.
  
  
• Companion tracks (harp, viola) can now be heard if you install the corresponding files (see "companion music" paragraph)

More about the changes made in the "Detailed changes.txt" file shared on the download page linked below.

This video should give you an idea of what it sounds like before and after (don't watch if you didn't play Journey yet !) :

Details about how the latest Paradise audio fix was made and what it sounds like:

Companion music mostly consists of additional harp and viola tracks played over default tracks (also includes a few other instruments in some areas).

Normally the game switches the companion tracks on and off depending on being connected to another player or not.
This feature as of today is broken in the PC version and no multiplayer music can be heard at all ! (a bug, with the exception of Pink Desert level where a bit of viola can be heard even when alone...) The multiplayer files exist but the game simply won't read them... It works as intended in the original Playstation versions of the game.

To solve this issue I instead merged companion tracks with the corresponding solo tracks playing at the same time. As a result, if you install the companion files you will have companion music on all the time, even if alone in the game !
Thanks Abhi for the idea of editing audio files this way !

It's worth mentioning that for a few locations within the game, multiplayer tracks aren't supposed to follow exactly an other solo music track in particular, and are supposed to be played over different solo tracks unheard together. Or sometimes companion music is supposed to stop the moment a new track appears, while the main solo track keeps on playing...
This cannot be efficiently reproduced by merging files, so some choices have been made regarding which tracks to merge companion music with or not.

Thanks to Yupa for helping me understand a few multiplayer situations ^^

Latest update v1.2.1: Paradise music fix added (Apotheosis).

v1.1: Syncing every audio files from Chapter Select to Snow level, and merging them for companion music.

1. Download the solo or companion audio files by clicking this Google Drive download link[drive.google.com] (or from Nexus Mods[www.nexusmods.com], if you got an account there). You can also download the Paradise level fix (Apotheosis) with 10 minutes or 1 hour looped audio files (heavier files)
   
   
2. Open your Steam "Streams" folder located at:
   
   \Steam\steamapps\common\Journey\Data\Sounds\Streams
   
   
3. Open the downloaded archive, select all ogg files (ctrl + A to select them all), and left click + drag them into the "Streams" directory from your game. Choose to overwrite files.
   
   Both the solo and companion music files can overwrite each other, to switch from solo music to companion music ! Choose the one you prefer (I definitely won't go back to solo music personally ^^)
   
   
4. Enjoy !

• You can do so by making a save of your original ogg files contained within the Streams directory of the game, before overwriting them.
  
  
• Or simply ask Steam to check for the integrity of game files to re-download them:
  
  Right click the game in Steam launcher --> properties --> local files --> Verify integrity of game files.

• Abrupt transitions. Many can occur on the second half of Pink Desert level for example or in Snow level, when the first loop just suddenly stops after a few seconds of overlapping with the new one. The game should add a fade out or fade in to many loops but it doesn't do it every time (or badly), and I can't make it any better with simply editing the audio files.
  
  
• Off-sync transitions (for example Apotheosis music in paradise, which is very complex: whenever a music track is supposed to start playing at a specific barline it just won't on pc and will instead start based on when you touched the music trigger)
  
  
• Player shout (chirps) and reverb: It does not fix the chirps and audio reverb, which is fine in the playstation version but bugged in the pc version (chirps don't sound as rich and are quite harsh to the ear)
  
  
• The companion music fix isn't a perfect solution in its current state