The Warsaw-based Royal Quartet have made their mark in Britain in recent years, notably as BBC Radio 3 Young Generation artists. Yet, in this opening concert of the Gower festival, the pressures of being such a busy and sought-after ensemble seemed to be showing.

Initially, the expressive slow introduction to Mozart's Dissonance Quartet, K.465 in C major, augured well, but after that, the playing was distinctly uneven, with extremes of dynamic exaggerated as though this were Beethoven rather than Mozart.

The Royal players sounded more attuned to the edgy tension of Shostakovich's Quartet No 7 in F sharp minor, Op 108, making the spare lines of the Lento raw and angst-ridden. After the incisive fugue and the ironic inflections of the waltz, the relative acquiescence of the final bars carried a sense of stoic resignation rather than resolution.

The quartet's most passionate advocacy was reserved for Grieg's rarely heard Quartet in G minor, Op 27. The music's restlessness chimed with the Royal's intensity of delivery, and the darker timbres of viola player Marek Czech and cellist Michal Pepol added resonance. Yet perhaps most striking was the vivid highlighting of Grieg's imaginative textures and harmonies. Not everything was high drama, though, and the lilting dance rhythms of the Romanza and the saltarello of the finale had a warm and, by now, rather welcome, exuberance.