Downloaded file is not equal to the original one

Origin url is http://ohwy83emy.bkt.clouddn.com/app_vedio/2017/03/08/1488947409951/1488947409951.mp4 which can be played through Chrome browser.

And in my application, wrapped url would like this http://127.0.0.1:36541/http://ohwy83emy.bkt.clouddn.com/app_vedio/2017/03/08/1488947409951/1488947409951.mp4 .

With IJKPlayer i can play with origin url, but cannot play with wrapped url.
I have did some tests, donwload from both two urls. The files are different.
The md5sum text of file from origin url is: 98fdf6fd427f78028445d2a857c9aadd,
however, the md5sum text of file from wrapped url would change sometimes, but never equal to 98fdf6fd427f78028445d2a857c9aadd. And the file downloaded from wrapped url cannot be played on my computer. It seems like the file was broken.
Well, both the size of two files are equal to 438140 bytes.

Can you do something for this?
Strongly depends on the library, great job of yours.

Thank you!!