Stornoway, Shepherd's Bush Empire, London

"As we're at Shepherd's Bush Empire, I thought it would be appropriate to tell you a story about sheep," says Brian Briggs, nervously, in the Oxford indie-folk quartet's signature style of banter. Stornoway's frontman rambles about a study on making lamb fat into fuel, which leads the lads into "Fuel Up" and gets a big laugh.

From the first notes of the upbeat opener "The Coldharbour Road", the four-piece display the jolly eclecticism that underlines their dreamy debut album, Beachcomber's Windowsill. Never far from their twee musical roots, "Here Comes the Blackout" features the drummer, Rob Steadman, beating two buoys the band brought back from Stornoway (not to be confused with boys, which Briggs's playful explanation makes less than clear). But despite Briggs's consistent vocal beauty, drum and synth levels overpower the usual twinkling subtleties.

With two masters and a PhD between them, as well as an endless collection of instruments lining the stage waiting to be played, it's clear that the lads are a smart bunch. Yet it often feels as though they're trying too hard to be clever. An unnecessary remix of "Long Distance Lullaby" detracts from the original, and a crowd of well-wishers dropping cutlery on the stage to create a crashing sound looks too contrived.

Performed with a spring in its step, the aptly named "The New One" offers promise of catchy Sixties-style folk but feels immature next to the stunning simplicity of songs such as "I Saw You Blink".

The cheery trumpets on "Zorbing" make it a popular autumnal anthem to end on as leaf-shaped confetti rains down on the crowd. But it's the unplugged, stripped-backed version of "We Are the Battery Human" that truly displays the magical delicacies, majestic strings and smiling humour that have made Stornoway one of the most promising new acts of the year. Let's hope they don't try so hard next time.