There is this one bug that you can't avoid or ignore which is in all mods that skip the starting sequence in pre-war Sanctuary Hills. Otherwise great mods like Another Life. I'm talking about the vertibird engine sound missing in such save files and therefore silent flying Vertibirds for the remaining playthrough.

After researching this issue I've found out that it's caused by the game only ever unmuting the engine sound when the Vertibirds in pre-war Sanctuary show up for the first time. (This happens at quest stage 400) Since they're already spawned in but you're not supposed to hear them yet. A simple way to fix this is to use console commands, and I'll give you a tutorial in text form right now. (Install a mod that enables the console in Survival mode if needed)
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Note: Please do backup your save files before attempting to apply the fix, just in case anything goes south. The default location for F4 save games is C:\Users\Username\Documents\My Games\Fallout4\Saves


New Experimental Method - Found by Cubox! (takes just a few seconds)

Hey guys, someone with Creation Kit knowledge looked into my former research regarding quest stage 400, isolated the specific cause of this bug and came up with a much more efficient way of potentially solving it.

1. Just type in "rscs 131b8d" into your console. As always without the brackets.

Command stands for Remove Sound Category Snapshot, and it'll remove the Sound Category Snapshot that is muting the Vertibirds in pre-war Sanctuary and which gets never taken care of by Another Life and similar mods due to never completing quest stage 400. (The removal can be undone by using the "pscs 131b8d" command)


2. (Optional) Spawn a Vertibird with "player.placeatme ff991" and listen to that sweet engine sound. (Click on it and type "disable" to remove it again)

Please award your kudos to the user Cubox for finding a better solution with the CK. And continue endorsing, so everyone can find this bugfix!



v In case the method above leads to any problems (i.e. missing ambience sounds or cyclic lags), you can revert to your backup save and try out the initial fix below. It takes some fiddling around with the console and HUD, but the method has been more thoroughly bug-tested by me and several helpers. v
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Original Tutorial - Step by step (takes approx. 15 minutes):

Note: Make sure that you've completed the Another Life intro (creating your character and leaving the synth chamber), aren't in the middle of a scripted quest and that you're in a place that you can easily teleport back to.

1. Open the console and type in "coc prewarsanctuaryext01". As always without the brackets. (This is more interesting if it's night in the game, since you don't usually play through the sequence at nighttime)

2. Open the console and type "tcl" to toggle noclip. Then go through the wall into the bathroom of your house. Deactivate it by typing "tcl" again. Note: Make sure you have no reference ID on screen. Like if you click something on the screen while the console is opened. Otherwise tcl won't work.

3. Play through the quest normally as if this was the beginning of the game.

4. If the Vault guy is brining up the character name and S.P.E.C.I.A.L. attributes screen, just press the R key to confirm. It won't change anything this way.

5. Wait for the TV guy announcing nuclear blasts and your home door opening. Quest stage 400 has started and the vertibird engine sound file has been loaded into the game.

6. IMPORTANT: Use the "coc sanctuaryext" command right after the door opened. Because if you exceed a certain time limit, a military announcement sound file will start looping unstoppably in all Sanctuary cells.

7. Wait 30 seconds and check if the military announcement is playing in after-war Sanctuary Hills. If not, you're good to go.

8. Only problem left is that said quest stage has started a music file that won't stop playing ever again due to us not completing the quest. Fix it by simply typing "removemusic musspecialchargenrunforthevault" into the console.

9. Now use the coc command to go back to any place you've originally been before. Here a list. Also make a new save file.

10. (Optional) Spawn a Vertibird with "player.placeatme ff991" and listen to that sweet engine sound.


>> But we're not finnished yet! Using this bugfix can break certain HUD elements, i.e. your health bar not showing up outside of Power Armor. So if you notice anything out of ordinary with your HUD, proceed to the next few steps to resolve this issue:

11. Download Immersive HUD - iHUD (LITE) and activate it from your mod manager.

12. Load your affected save file, go into your Pip-Boy and search for the Settings Holotape of iHUD. It's in the INV category under Misc, all the way down.

13. Just activate and deactivate iHUD once through the tape, this will completely reset your HUD.

14. Make a final save file. At this point you don't need iHUD any longer, but it's of course up to you what you do henceforth. :D

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Here you go. Doing this shouldn't affect anything outside pre-war Sanctuary and Vertibirds finally have sound again! I've tested this on my personal save.

Thanks to malakengago, Blender123 and Monster_Hunter for the insightful bug reporting!