PCSX2 version:
1.5.0-dev-2237
PCSX2 options:
Plugins used:
All default, no speedhacks, following GSdx settings:

Description of the issue:
Frequently, your car's engine will have this annoying crackling to it. It seems to happen most often when I go into a race with software mode.
https://www.youtube.com/watch?v=LiTBlEJnd94
The mods aren't the cause of the issue. I get the problem with an unmodified copy, I just happened to have the modded copy selected when I was recording the video.
How to reproduce the issue:
Go into a race with software mode enabled.
Last known version to work:
Issue has always been present.
PC specifications:
CPU: i7-7700K
GPU: GTX 1050
OS: Windows 10 x64
RAM: 8GB
What about your SPU2-X settings?

DirectSound is obsolete now, a lower latency with XAudio2 and ASync Mix or None would probably work better.
Use Directsound only if you have a very old sound card wich does not support Xaudio2 (the Directsound succesor).
I'm not sure to which windows version you have been left, but sound card has nothing to do to support windows's apis.
I can't reproduce this on my NTSC copy, disable the de-alias filter that you were using in the video and/or check your sound card's drivers.
FWIW, my Creative sound card will randomly start crackling whenever Windows feels like it, which forces me to disable and re-enable the output device in the Sounds->Playback tab. That could possibly work for you as well
I found now it's definitely because of DirectSound. I think the "nice" tag beside the DirectSound option is misleading as it implies it's better in some way than XAudio, which is only "recommended", which is the reason I was using DSound (I'm not really an audio guy.)
Ok I'll close this then.
Reopening since I am able to reproduce on 1.7 with certain race events using XAudio or PortAudio. Settings don't seem to affect the issue.
Most helpful comment
DirectSound is obsolete now, a lower latency with XAudio2 and ASync Mix or None would probably work better.