FSSound problem ... help me, please

Hy all,i've a big problem using FSSound for a looped sound.I've already use in the same gauge the same function in "single play" mode and gauge playing the sound correctly.This is the code for single play, using FALSE in the MFSSoundFilePlay macro :-=-=-=-=-=-=-=-=-BOOL FSAPI doors_disarm(PPIXPOINT relative_point, FLAGS32 mouse_flags){ lookup_var(&panel_circuit);MFSSoundFileRegister(sound_doors_disarm);if(panel_circuit.var_value.n != 0) { MFSSoundFilePlay(sound_doors_disarm, FALSE); } return FALSE;}=-=-=-=-=-=-=-=-=-Now, i've a problem using the same macro with TRUE. In this case i'll expect that when i click on the linked button, the gauge will start a looped sound until i'll press the button already.This is the code ...=-=-=-=-=-=-=-=-=-=....MFSSoundFileVars(sound_air_cond,"SOUNDcabin_callssound_air_cond.wav");........MOUSE_PARENT_BEGIN( 82, 374, 26, 26, 0 ) MOUSE_CHILD_FUNCT( 0, 0, 26, 26, CURSOR_HAND, MOUSE_LEFTSINGLE, air_cond)MOUSE_PARENT_END....BOOL FSAPI air_cond(PPIXPOINT relative_point, FLAGS32 mouse_flags){ lookup_var(&panel_circuit);MFSSoundFileRegister(sound_air_cond);if(panel_circuit.var_value.n != 0) { // start or stop a looping sound buffer if (MFSSoundIsPlaying(sound_air_cond)) MFSSoundStop(sound_air_cond); else // specifying TRUE as the second parameter in the play function (macro) // makes the sound buffer loop forever or until the stop function // (macro) is called MFSSoundFilePlay(sound_air_cond, TRUE); } return FALSE;}-=-=-=-=-=-=-=-=-=With this code, when i press on the gauge button nothing happened !!!The .wav sound is correctly named and is in the correct directory ...Can you help me to find where i wrong ????Bye, Stefano