This doesn't answer your question, but most DirecTV receivers and DVRs draw nearly as much power when "off" as when "on". Find yours here: http://www.energystar.gov/ia/products/prod_lists/set_top_boxes_prod_list.pdf It may be easier to just leave it on.
The reasons are complex; see discussion at http://www.dbstalk.com/topic/189358-receiver-power-consumption/
I understand how having that power button more accessible to you is important. Unfortunately the location of the power button usually depends on the application that you use. For example the Sling Media website on the PC, the iPad & the Android Tablet all have a pop up on screen remote. That remote will resemble the same skin as the physical remote that you have for your cable box. The iPhone & Android Phone application have a whole different layout.
As for the audio only settings questions. None of the applications save settings of what you recently had it on. It automatically goes back to it's default settings.
This link below will give you a better understanding of where everything is for the mobile application to further assist you.
The remote controls for the Android Phone & iPhone are basically almost the same layout so refer to this post & it should further assist you.
I hope this information helps!
The Sling Moderation Team
I am talking about the iPhone app - the ipad app is fine. When I pull up the remote why do I have to scroll so far the find the power button ? Why don't you make it available without scrolling ? There is no priority attached to the order of your buttons. You need to read a book called 'the lunatics are running the asylum