Hi all. I have to say I like everything about this GK MB115 amp EXCEPT one thing. The metal grill makes rattling noise even at a moderate volume. I thought of putting some padding around the grill and tried to take the grill off. However, even after taking those 4 screws holding the grill (2 screws on each side), the grill didn't even budge when I tried to pull it out. So, I am wondering if there are any screws/tabs that I've missed. I could only see the 4 screws, but any chance there were more that I missed? If you can provide me with help/instruction on how to remove the grill on GK MB115, I will really appreciate. Thanks~!!!