Vehicle sound gets choppy when rendering a portal.

Immersive Vehicles Base
Immersive Vehicle Official Vehicle pack

Which BP version is this? There have been at least two changes to how sound works with portals since 0.1.

Latest release for 1.12.2 on twitch

Please be specific. I'm not using the twitch launcher and CurseForge is horribly ambiguous with which versions actually end up there.
For all I know, the latest version is 0.2.3.

Ah, I my apologies. I seem to be using version 0.1.6

I guess I'll update and see if the issue persists

Is there an easy way for me to get the latest version without needing to build it myself?

Actually latest version (i.e. git master) you'll have to build yourself (there were only performance and visual fixes though).
The latest release is available on CurseForge: https://www.curseforge.com/minecraft/mc-mods/betterportals/files/2743806

When I tested the new version with my full modpack it crashes with this error

So I removed a few mods to where I felt they should be compatible, but it failed again with basically the same error

Here's a more comprehencive list of all the mods installed when the second crash occurred:
Air-Cooled Pack [MTS] 1.10.2-14.0.0-BETA 1.0.0.jar
ArtemisLib-1.12.2-v1.0.6.jar
AutoRegLib-1.3-32.jar
betterportals-0.2.3.jar
BlackThorne Civilian Vehicles [MTS] [IR] 1.10.2-14.0.0-1.5.0-2.0.1.jar
BlackThorne Military Vehicles [MTS] [IR] 1.10.2-14.0.0-1.5.0-1.0.0.jar
Bookshelf-1.12.2-2.3.585.jar
CraftTweaker2-1.12-4.1.19.jar
CreativeCore_v1.9.54_mc1.12.2.jar
DimensionalDoors-3.0.9-287.jar
Forgelin-1.8.3.jar
GameStages-1.12.2-2.0.115.jar
Hats-1.12.2-7.0.2.jar
Hwyla-1.8.26-B41_1.12.2.jar
iChunUtil-1.12.2-7.2.1.jar
Immersive Vehicles-1.12.2-14.3.1.jar
ImmersiveCables-1.12.2-1.3.2.jar
ImmersiveEngineering-0.12-89.jar
immersivepetroleum-1.12.2-1.1.9.jar
ImmersiveRailroading-1.6.1_1.12-1138.jar
ItemPhysic_Full_1.4.21_mc1.12.2.jar
jei_1.12.2-4.15.0.287.jar
mekanica-1.12.2-1.2.0.jar
mekanica-generators-1.12.2-1.2.0.jar
mekanica-tools-1.12.2-1.2.0.jar
Moonspire Metropolitan Motors [MTS] 1.10.2-14.0.0-1.0.3.jar
MouseTweaks-2.10-mc1.12.2.jar
MTS_Official_Pack_V11.jar
TrackAPI-1.1_1.12.jar
UNU Parts Pack [MTS] 1.10.2-14.0.0-2.0.1.jar
WailaHarvestability-mc1.12-1.1.12.jar
WailaStages-1.12.2-2.0.23.jar

I'm going to try it with mekanism instead of mekanica to see if that is the issue
Yup, that was the issue. I'll check for the original errors now

Seems like sound is less annoyingly choppy in 0.2.3, however it's still choppy