GOVERNMENT House appears to be vying with the Cultural Centre for top spot in the musical stakes. At 6.30pm tonight, the Hong Kong Academy of Performing Arts puts on a classical and Chinese music concert in the House's ballroom. Then on March 23 and 24, the European Chamber Opera (ECHO) will stage a performance of Mozart's Cosi fan tutte, a delightful comedy about the supposed fickleness of women. Sadly, the March 23 performance, a gala night, is sold out possibly due to the added attraction that the Pattens and Lady Purves, wife of Sir William, will be in attendance. The last time ECHO were here was in September 1993 when they performed The Magic Flute in the garden of Swire boss Peter Sutch's Peak house. Following that, a public performance was held at Government House attended by Chris and Lavender Patten, who led a standing ovation. Tickets priced $750 are available from Treats on 2889-1332. OVERHEARD at Jimmy's Sports Bar and Grill in the Hong Kong Stadium: 'I've just been to the toilet. Do you know they put ice cubes in the urinals? It must be how they make Ice beer.'