It seems to be. Multiple people have resorted back on here saying the same thing. Although it might be this run through with this specific manufacturer (Klyde).
Over on XDA forums they cover all android units made by various manufacturers that are resold by companies such as Eonon, Joying and Pumpkin. All the 5.1.1 that have issues with also have screen issues, but there's is "low angle" viewing issue. This is just dim no matter what angle you're at.
The Joyous version of these units don't seem to have this dim issue, as I haven't seen anyone really talk about them and they've had the same rk3188 and 1024x600 panels. So I believe it was a manufacturing problem from klyde. But who knows. Pumpkin uses Klyde as their manufactures too but I haven't seen any complaints on their screens for dimness, maybe eonon replaces the screens lol.
Regardless these are just assumptions I've come up based on a good handful of people acknowledging the problem here on this forum, and what I've gathered over on XDA. Eonon can input some info or clarifying if they'd like.
Hi davidgotmilk, thanks for your concern, our unit has independent brand and design, which is quite different from other OEM companies. But thanks for your advice, today I’d like to announce a good news that, our new batch of GA6163F is released with brighter screen, it’s now fixed, the screen is quite clear and bright. Davidgotmilk, if you are not very satisfied with your unit brightness, we can provide you software to upgrade, I’ll send it to you as soon as I get it, thanks a lot!
I am hopeful that the problem will be solved as I have looked at some of the other products on Pumpkin and might go with them instead. However, I will wait a little bit and hopefully Eonon will have a response to this soon.
Hi mazda3415, thanks for your interest to Eonon unit. We definitely value you guys’ feedback. As I’ve mentioned before, the previous issue has been fixed on the new batch of GA6163F Android 5.1 Mazda 3 navigation
released yesterday, now they’re with brighter screen. Welcome to order it, now with free camera provided, and even up to 20USD lucky coupon
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