First point.
There is NO WAY you are getting the lap times you have been posting without hacks, bugs, exploits, voodoo magic, or a combination of these.
Second point.
The other issue is intent, as in, do you have intent to cheat or are you (like other players) getting a massive advantage without any explicit knowledge.
It is going to be up to you to figure it out, and trust me, you can figure it out real easy by trying to achieve your own lap times on an alternative account. Because at this point, there is no use in trying to fool other people there is no problem. The question is, are you going to delude yourself. That is why it sucks for you - that PD created a broken product. If you go through the entire thread, you can see how one player had to deal with all this - I do not envy anyone stuck with this problem as the game is by nature competitive and social.
Here is the evidence as it relates directly to you.
You have been consistently posting top #1 times in Asia Pacific (and setting WR times) using a DS, without analogue acceleration or braking, using automatic transmission and multiple assists. That alone is sufficient to warrant all the attention. Using AT alone rings alarm bells! Replays of your hotlaps are public, and people try to emulate your times. Impossible to do. Seriously, and this is going to sound harsh, but you must be in complete denial if you think your mad skillz alone are letting you consistently beat the best players in Asia.
We now have a number of players worldwide who seem to exhibit remarkably similar things to you, and some of those players can now attest to the fact that something has been broken for them. At this stage nobody knows exactly what the issue is, or how to replicate it.
To make it clear that this aint about YOU it is about the broken game that we all want to enjoy, we have two absolutely game breaking issues that are currently live and have gotten ZERO response from PD:
1) the 'grip' bug
2) majority of the tracks are still exploitable with pit area glitch (park your car near pit entry for 20 seconds and you get first position, lap incremented by 1) in ALL modes (including cup events)
Both of these render the idea of a competitive esport absurd. Indeed, the whole premise of the game as it is sold and marketed is fraudulent.
So, you have been given the information, up to you to deal with it. This is where it really is all about you, because how you decide to deal with this is going to be about more than just playing a video game. I am sorry you have to go through this.