Google problem..
From what I'm reading it's a google problem.. I have the same problem "AT THE SAME TIME" on my tablet and my mobile... maybe my isp, my router,
I can't post links.. but the problem it's fixed now.. How you say? A super ultra fast call to my ISP.. they switched the channels frecuency.. (Yes, I could have done that.. but I was intrigued why on the same devices at the same time.. but NO.. if on my cell phone I used the 3G (it's from other company) So I started thinking.. maybe the gateway, proxy.. etc. you name it..
So the problem was with the wifi channel.. don't ask me.. I'm just posting this for those trying everything.. and this one.. worked for me. (On both devices)
ps. of course, I can't be sure if they did something else... that's what they told me.. edit: A closer look to the router.. told me.. that they in fact DID something else.. because it's the same channel.... !!!