Outputs 3/4 and 5/6 Swapped
There is always a potential for outputs 3/4 and 5/6 to be the wrong way round on a 6- or 8-channel sound card. This is not a bug but an inconsistency in output routing standards. For example, on a 7.1 sound card the outputs may all be correct, but on another 8-channel card that's not described as '7.1 surround sound' but as '8 channel multiple output' or similar, then outputs 3/4 and 5/6 may be the wrong way round.
If you find your outputs 3/4 and 5/6 are the wrong way round then there is an option you can set in Options and Settings - Audio Driver - DirectSound/WASAPI. This is labeled Swap speakers 3/4 with 5/6. If you change this option you may need to close and restart SCS for this to take effect. Please note that this option is only used for 6- and 8-channel sound cards as these are the only configurations that have the problem. Also, it is not used with ASIO outputs or with the SM-S audio driver.