Thanks for coming back to me but I don't think we're there yet - it's not Cali pachanguero, and I can't find the MP3 player on salsaatl (may be because I'm not in the US?) but I found a clip on another site and I don't think that's it (but having not heard the remix I'm not sure). The bit in the middle where they clap the clave beat you virtually lose all the rest of the music, there's virtually no singing and they just focus on the clave beat - not sure if this helps? I've been listening to too much salsa now, I can't even get the tune back in my head! If I get it back and think of anything else I'll let you know!
Is the song possibly "Amor Mio No Te Vayas" by Gilberto Santa Rosa? I haven't heard the song recently enough to remember how "brassy" it is, but I do recall a part of the song where most of the instruments disappear except for just the bass and something that sounds like a clapped clave.