Rotel surround receivers have several different 6.1/7.1 surround formats available for digital sources – Dolby Digital EX, dts ES, Dolby Pro Logic IIx and Rotel XS Expanded surround. The Rotel receiver will "remember" the last used 6.1/7.1 processing mode it was set to and will use that as the default each time the same format is received. For example, when listening to a Dolby Digital 5.1 soundtrack the mode is set to Dolby Digital + PLIIx to use Pro Logic IIx to add the additional rear channels.  The next time a Dolby Digital 5.1 soundtrack is played the receiver will swicth to Dolby Digital + PLIIx automatically. A separate default is remembered for dts soundtracks as well.

To switch the default mode, when listening to a Dolby or DTS 5.1 soundtrack, press the 'SUR+' button, following by the ‘+’ button on your remote control to cycle between the available surround modes. Changing the mode in this way will set this as the default 6.1/7.1surround mode for all future Dolby Digital / dts sources.