I recently purchased a new sound card ASUS Xonar STX, this is my first ASUS sound card, the "problem" Is the back looks very greasy is this usual?, i never had seen a PCB greasy on other hardware (videocards, motherboards, expansion cards, etc.), also has a strong odour, I could remove grease...

I have the same card, and i noticed that there were differences seeing pictures reviews, no thorough investigation, the only thing I noticed is that they have changed the PCIe bridge PLX8112 to Asmedia 1083 and Sanyo power capacitors, but seems there no quality loss.