Cannot remained logged-in on my iPad, why?

[intheozone]

Help needed. Previously I was able to stay logged-in all the time on my iPad 2 (running the latest software update) but now I have to sign-in each time I opened the iPad browser to DU. This has been going on for the last couple weeks. I have tried completely logging-out and then logging-in again, but that didn't help. I use both Safari and Firefox on my iPad and both have been logging me out.

I have no problem staying logged-in on my iMac desktop, but can't get the iPad to keep the log-in, even though I check the "Remain logged-in" box.

Please, some body help me figure out what is going on and how to fix it. Is this a problem with the DU or with the iPad?

The ads when not logged-in are driving me nuts.