knusperhirsch

For the future, for whoever uses the search bar and finds this topic, here is your answer.
Dull lights can be caused by:
- Having Shaders not set to High/Ultra, same with PostFX.
- Not having Radiance V.
Glad you got it fixed. 

But as I said, that topic isn't returned when you search for the terms related to this topic. It's clear you still haven't actually used the search bar to see for yourself why your advice was useless in this situation.

Regardless of whether or not they're similar problems, they may not appear to be the same to someone inexperienced. As well as this, just because something has a similar solution doesn't mean you're going to look in the same place for the answers.

Your topic does not mention Radiance V or Visual V. How on earth do you expect someone to go into that topic, find a different problem, which states a different solution and then infer an answer is beyond me!!
Also, in that thread regarding White lightbars:

That's not even the solution for this users problem. Your guide has nothing to do with this!
No shit detective?! That's why they're asking for help. If they knew it was installed incorrectly, you think they'd be asking for help?

Not only do you give the advice to use the search bar which doesn't necessarily yield results, but you also link to a long ass guide that doesn't contain the real solution to their problem.

I understand what you're saying about the search bar, but I've just searched "lights dull" in the search bar and nothing helpful is being returned apart from "Install Radiance V and Visual V" as the OP has already done. Before suggesting they search, maybe check to see if there are helpful results when you actually do search first?
http://www.lcpdfr.com/search/?&q=lights dull

I also don't see anything about dull lights in that guide of yours, only how to correct an all white lightbar.

Thank you soooo much!!!  I followed your tip and installed Visual V first (this time with the package installer and not the manual install) and after that Radiance V - now it works like a charm! /hug
 

Did you install RadianceV after installing VisualV? VisualV replaces the same file that RadianceV replaces, so be sure to install RadianceV second. Also, make sure, if you're using a mods folder, that you've placed the files in the mods folder. If you have the visual settings file in the mods folder but you replaced it outside of the mods folder, it will use the file inside of the mods folder.

http://www.lcpdfr.com/files/file/7798-gta-5-realistic-american-sirens-new-fbi-and-granger-sirens/?page=6&tab=comments
 
There's a fix there and if you go to the next page someone made a more clear way to do it.
however i will put what he put here. I did not find this so go thank John23 also Kilyin for making it simple
Do this:
Export your current vehicles.awc as openFormats to a blank folder with OpenIV. In that folder, replace all the files in \vehicles with the .wav files from the siren mod you're installing. Now with OpenIV reimport the .oac file from said folder. That should be all you need to do as the latest OpenIV update fixed the issue with importing the sound files.

EUP uses a GTA Online ped model, which doesn't have any speech. To get a voice, you need a trainer that has an option to select voices and select a cop voice.

You have to select your custom officer with EUP and THEN go on duty by opening the rage console and typing ForceDuty.
EDIT: Alternatively, you can use this mod.