Hi, since a week or so I'm experiencing very slow resolution times. 

I've Investigated with a sowftware called internet-pi hosted on a raspberry that constantly perform network testing. I've didi because I was convinced that the problem was on the ISP side. 

Today my internet provider borrowed me another router and I've attached the raspberry to the new router:

The http resolve time is strangely constant.

From about 17.50 to 18 the raspberry was off, then was reattached to the new router (you can see fast resolution time), and then I've reattched the deco and gone back to bad results.

I've tried changing DNS server but the time remain constant. 

Raspberry is connected via ethernet. 

The firmware is updated, and I'm thinking the unit has some sort of failure, don't know if hardware or software. I own this system from about 6 months, and till know it worked, even if I had some doubt because I've changed it when I've changed ISP and I had some issue here and there. 

I've bought it through Amazon and thinking of returning it. 

Someone has faced similar issues? The last try I'm going to do is to switch the main unit with one I have in another room.