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I have 3 Rokus in my house and HBO Go is installed on all 3 of them. Starting with the recent "new" app upgrade I've ran into an issue. If I activate only 2 of them there's no problem but if I activate the 3rd one the first two get logged out. Then if I reactivate the 1st two the 3rd one gets logged out. And I'm not talking simultaneous streams, I'm talking just being logged in to see the watch list, etc. I don't have this issue with any other providers so is Cox limiting how many devices can be used?
I would suggest changing your HBO Go password and trying again. HBO GO only works on 3 devices I think, so if someone else is using the password for a 4th device, even if not on your network, it may be causing a problem. Also make sure your not using a sub-account, and using the admin(first) username/password on the Cox account.
There is no password for HBO Go, when you sign in it takes you right to the Cox login for authentication (my one and only account I have-admin) and I change that password regularly. Also not using a sub-account. I did contact HBO Go and Roku first and they both responded that login issues are tied to Cox which is why I posted my question here.
Oops, confused HBO Go with HBO Now.
When you change the password, and enter the new password into the 3rd device, does it disconnect the other two devices? The situation would appear to be there is some 4th devices that is connected with your credentials, and since the limit is 3, it disconnects one when you try to connect YOUR 3rd device.
Can anyone from Cox confirm if HBO Now applies to secondary Cox usernames? I thought it was admin only, but maybe if it's not, someone is using one of your secondary usernames to access. If you don't have many usernames, might not hurt to change the passwords to those too. I just wish Cox had some way to check who/what is logging into your Cox account and from what IP like they do for gmail. I don't even think Cox employees can see that, Tier 1 anyway.
I re-read your OP, and I think I have a different idea. The fact that it isn't giving you the typical "Too many users" message, and the fact that it's signing out BOTH units, not just the possible 4th one, makes me think something else is going on. I wonder if your router or network is only able to keep the connection open for 2 devices at once. Can you try accessing the HBO Go app from your phone when NOT on Wifi? I wonder if it will allow the 3rd stream if not initiated on your local network.
Yes, anytime I activate the 3rd device the other two get disconnected. I wonder if there's a limit of 2.
I've never owned more than 3 Rokus. In fact they're still the original streaming sticks; I've never upgraded them because they work just fine. I don't have any additional Cox usernames nor have I ever given out account information to anyone. I take care of everything so the household just has to fire up the Roku and start streaming. I don't own a smart phone (nor does anyone in the house) so I can't test your phone app theory. And, yes, having an authorized devices list in my online Cox account settings would be grand.
We're a household of seniors and we don't go out much except for doctor appointments and grocery shopping so TV is our major entertainment.