Hi @dibb — Thank you for the report and my apologies for the troubles. I went ahead and split your post into a new topic so we can address your specific issue(s) more directly 
Besides, the Airport extreme and the Technicolor router (TG582n), are there any other networking devices you are using? If so can you verify that information for me and provide a description of what the chain of communication looks like in your home network? Can you provide some further details about your setup, as seen here?
Since noticing this behavior have you tried reinstalling the remote application on those devices? Does power cycling your equipment (router included) help, even if it is temporarily?
-Eric