rodents getting into speakers via speaker ports

I was told by my pest control person that a mouse can get thru a hole the size of a dime, and a rat would be a nickel. Also, the only thing they will NOT chew through is metal, so I have stuffed steel wool in ANY hole I can find on the outside of the house that is a dime or nickel size. We live in western NC, and LOTS of rodents here. 

Interesting to watch the man remove the Cobra, but we have a cat to take care of other rodents ...

@elliottbnewcombjr The mice don't eat the wire insulation because they're hungry. They do it to sharpen their teeth. Just thought you might find that interesting.

@dmk_calgary A rat certainly can and will chew through metal. I've read that a rat can eventually chew through steel if it's life depends on it. 

I had a bat fly out of the port on my SVS sub in my office system.  Mt house is 105 years old and there are woods behind my house. In 2002, I found 2 bats in my home and had a professional remove them and fix the eves where the bats were getting through. That lasted until I had a new roof installed in June 2020.  Unknown to me, the roofers removed all the blockage under the eves and dormers. A year later, they were back.  This time there were 3 of them, one that flew out of the port and 2 in my living room.  I called another professional and had my house de-batted once again.  The first time in 2004 it cost $1000.00, in 2021 it cost me a little over $2500.00.   I had the company that removed the bats the second time come back last year for a check and the house is clean.  Nothing scared me more than having a bat come out from nowhere and fly right in front of my face.  I can still hear the flapping of their wings and the feel of the air moving in my mind.  It’s hard to shake.  

If you believe AI.........

Soft Metals They Can Chew Through

Because a mouse's front incisors never stop growing, they must constantly gnaw on materials to wear them down. They easily destroy softer metals: [1, 2, 3, 4]

• Aluminum Foil & Screening: Standard kitchen foil and lightweight aluminum insect screens offer no protection.
• Thin Gauge Aluminum: Low-gauge sheeting used for gutters or flashing can be pierced if a mouse finds an exposed edge. [1, 2, 3]

Hard Metals They Cannot Penetrate [1]

To effectively rodent-proof a structure, professionals rely on harder metals that shatter or dull a mouse's teeth if they try to chew them: [1, 2, 3, 4]

• Galvanized Steel Hardware Cloth: A wire mesh with openings of 1/4-inch or smaller is the standard for sealing vents and crawlspaces.
• Stainless Steel Mesh or Wool: Stainless steel is incredibly dense and resists rust, making it an absolute barrier.
• Heavy Sheet Metal: Thick iron or steel plates used in heavy construction cannot be breached. [1, 2, 3, 4, 5, 6]

A Note on Steel Wool and Copper Mesh

While mice physically can pull apart or eventually gnaw loose strands of steel wool, it is highly abrasive and hurts their noses and mouths. They will generally avoid chewing through tightly packed mesh plugs. To prevent them from simply pushing or pulling the mesh out of a hole, pest management professionals recommend embedding the steel or copper wool in caulk or expanding foam to create a permanent, unified barrier. [1, 2, 3, 4, 5]

interesting rabbit holes - pun intended - we end up going down...... I have some work to do this summer on my steel wool 'solution'