[LAU] Check compliance of SF2 soundfont

Hi, I bought samples from Dubsounds in SF2 format, and looping is wrong when rendering with fluidsynth. I'm wondering how to check whether this is caused by buggy files or a bug in fluidsynth. The symptoms: -- in fluidsynth (command line, qsynth, Calf plugin, or Carla), I can hear that looping is wrong -- there is obviously a gap -- in swami, the start loop point seems ok, but the end loop points is beyond the end of sample. When loading the soundfont, it spits a bunch of "libInstPatch-WARNING **: Invalid loop for sample" on the console -- in polyphone, it loads and plays ok. Loop points are perfect. Is there some extension or advanced feature that polyphone supports but not fluidsynth nor swami? How may I know who is the culprit? Here is the output of sf2dump: http://pastebin.com/CthdwrQf Thank you, -Alexandre.