I am planning to connect my new PC build (Mb is an Asus ROG Strix b550f) to my old panasonic 5.1-channel home theater system. I checked both manuals, and Asus shows how to connect the PC to different audio system types in the manual. One of these is 5.1 channels, but the Asus diagram assumes three input ports on the Sound System whereas I only have 2x RCA and 1x 3.5mm input options on the Panasonic. I will use a standard 3.5mm jack for output from the PC. Should I use a 3.5mm to 2x RCA cable OR a 3.5mm to 3.5mm to connect my PC to the Sound System? I would like to have 5.1 channels if possible. Does the 3.5mm cable support that in one channel? Is there another method I should try so I can have full 5.1 surround?