Presumably you use a USB cable from your PC to your DAC? so I wouldn't have thought you could get a USB cable anywhere near 7 mts long, so you're probably going to have to have some RCA leads made up to run from the DAC to Amp.
Linn Axis tt/Akito arm/Nagaoka MP200 or ATVM95/ML carts/Trichord Dino mk3 phono stage/dedicated PSU
Marantz CD6006/Cambridge 650T DAB
Tisbury Mini Passive II pre/Roksan K3 Dac/Roksan K2 integrated used as power amp
Atlas Element Integra Superior inter-connects
Spendor SP1s(1988)/Van-Damme UP-LCOFC HiFi 4mm cable