Apropos of nothing, Georgian-born chanteuse Katie Melua surprised everyone with 2010's The House by hooking up with William Orbit and fusing her familiar brand of coffee table jazz-pop with flourishes of subtle electronica.

Perhaps concerned that it failed to top the charts like her previous three records, the 27-year-old has reverted to type for its follow-up, Secret Symphony, by returning to mentor Mike Batt, the former Wombles songwriter responsible for her incredible early success.

It's a disappointing and frustrating retreat back to safety.

Melua's distinctive velvety vocals were always more intriguing than the so-laid-back-they're-horizontal arrangements which surrounded them, but her last effort was an encouraging sign that she could leave her usual dinner party background music firmly behind.

And while Batt's contributions here -- such as the drowsy lounge pop of "The Bit That I Don't Get," the steel-laden country balladry of "The Walls of the World," and the yearning, string-soaked title track -- are all typically elegant, demure, and understated affairs, they're so overly polite and ultimately anodyne, they make Eva Cassidy sound like a death metal act.

If any more evidence were needed that Batt appears to be restricting her talents, Melua is far more captivating on the self-penned chamber pop of "Forgetting All My Troubles," and the four cover versions included, from the soaring torch song reworking of Ron Sexsmith's "Gold in Them Hills," to the double bass-led shuffle treatment of Fran Healy's "Moonshine," to the straightforward rendition of Françoise Hardy's sultry chanson "All Over the World." Secret Symphony is therefore not without its charms, but ultimately it's a clear step backwards from an artist who appeared to be overcoming her notable lack of edge.