Default Galaxy tab 3 10.1 refurbished

Hello everyone, hope someone can help me, I bought a refurbished galaxy tab 3 10.1 from ebay.
The tab runs smooth in general the trouble I find is that does not recognice my usb otg cables or keyboard, I have a galaxy s3 that does support usb otg and have tried 3 different ubs otg cables and a keyboard and none is recogniced by the tab but yes on the GSIII.
Today while trying to view a video from the chrome browser got a message html5: video file not found. so I tried the stock browser and while I don't get any message it doesn't plays the video.

¿can someone confirm if the usb otg is supported? and lecture me about the html5 issue.

or did I get a faulty unit.

Thanks and sorry for my english is not my native language.
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