For those accustomed to tropical weather, it was warm; for the Mainland musicians, it must have been stifling.

Violinists Cecily Ward and Tom Stone, violist Ethan Filner, and cellist Jennifer Kloetzel filed on stage in formal dress, already looking flushed, and the men removed their jackets.

Even so, the beginning of the Mozart was uncertain, intonation fluctuating wildly. The quartet stopped in mid-movement, and first violinist Ward explained that she was having a reaction to the heat. She was shaking too badly to play and feared she might fall off her chair.

While she took a break to recover with the help of ice packs, Stone, Filner and Kloetzel entertained the audience with tales of other concert mishaps and with information about their schedules, bows and instruments, including a 1681 Stradivarius violin and a 1734 Bergonzi violin. (The cello, "Gertrude," gets her own seat on planes and accumulates frequent-flier miles.)

Finally, a maintenance crew restarted the air conditioning, while the audience and Cypress Quartet took a pre-concert intermission so the hall could cool.

The second time around, the concert ran as planned, each movement becoming more secure. By the middle of the Bartok, Ward seemed back at full strength, and communication flowed smoothly among the four musicians, engrossed in their music.

Kloetzel and Filner provided a firm foundation for the ensemble, Kloetzel's tone especially vibrant and Filner's voice beautifully expressive. Stone wove between them and Ward, his warm tone working equally well whether as an internal or as a primary voice. By the end of the concert, Ward led with assurance, her tone bright and clear.

The eight years the group has worked together were audible in their nuanced interactions, their ability to listen and to adjust moment by moment, and especially in their mature interpretations.

When clarinetist Anderson joined the ensemble, he integrated his lines seamlessly. Anderson has a velvet chalumeau (low-register) tone, and he opened the Brahms quintet with a lovely crescendo before tapering into a gentle caress. Although his tight control narrowed the tone in his uppermost register, he excelled in high, pianissimo and sensitive passages.

The concert lasted a full hour longer than expected, and some in the audience had to leave at intermission. Those who stayed, however, rose for a standing ovation, grateful for having heard the entire program.