Blurry texture like 99% scale?

Hi everyone,
i got the problem with the big texture( 2048x2048 ), it’s rendered correctly, but the quality is blurry abit( like 99% scale ). some ways that i already tried:
- check the filter ( make sure GL_LINEAR )
- enable CC_FIX_ARTIFACTS_BY_STRECHING_TEXEL 1,
- check out the game logic, make sure no dump code, scale it to 99%
Anyone saw it before, any code, hint, or experience would be appreciated
p/s: i am using cocos2dx 3.2, for some reason, i can not upgrade to the lastest version
Thanks in advance