This is the third mini-festival curated by the xx under the banner Night + Day, following events in Lisbon and Berlin. If there is a tone, it is set by the hosts: artfully moody electronica is in generous supply. But there are exceptions, both on the main stage and on the bandstand where the DJs – including Jamie xx – confirm that late-70s/early-80s dance music is back.

Night + Day, as befits its title, alternates between the two moods. London Grammar's downtempo electronic pop, sung soulfully by Hannah Reid, is well received, even if it is a little too patly post-xx. Jon Hopkins unleashes sublime waves of glitchy, haunting sound from his laptop. Mt Kimbie specialise in quiet storm electronica, although their music can, at times, sound like anything from post-rock and krautrock to prog rock. Poliça maintain the middling tempo and sepulchral ambience almost too well, and after a while Channy Leanagh's tremulous vocals start to grate.

Kindness, a UK funk troupe fronted by Adam Bainbridge, a skinny long-haired dude who looks like a refugee from a grunge band, are a superb deviation from the chilled grooves. Theirs is a knowing but not ironic take on exuberant disco and funk, and it is greeted suitably enthusiastically. It could be their time to get lucky. Solange, sister of Beyoncé and the R&B darling of the leftfield, offers another respite, jerking and lunging where the other acts have been mostly inert. Benji B's DJ set is arguably the night's highlight, a stunning mix of hip-hop, grime and garage that gets a frenzied response. The area is bathed in white light for the xx. While once they were tentative, now they have emerged from the shadows: if anything, Romy Madley Croft and Oliver Sim's vocals are too confident. And theirs is an efficient, politely emotional form of dinner-party dubstep. Time, perhaps, for them to blow their cool apart with some of that disco and funk.

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