the HD621 is just for HDMI input which the squeezebox doesn't have. if you're just looking at network streaming then I guess it would be a squeezebox into a G61r/G68 vs a linn DS akurate. I'm afraid I've heard (and indeed own) the former, but not the latter.

dave

Lounge: LG 55B6v, Some Denon receiver, Anthony Gallo Reference AV mains, Totem Dreamcatcher centre, SVS PC-4000, AppleTV4K
Office: Audioquest Dragonfly, Cyrus 6DAC, Monitor Audio CPW Gold
Headphones: NuForce HDP, Audeze LCD-2, Sennheiser HD6XX, B&O H6mk2