Slow internet speeds. Ingress/Egress in Coax cable

I've been having some slow internet connections at my house. Called Cox tech support and they said I had high packet losses. They sent a tech out and he said that I am having some "leakage" from the cables. He said it is probably some staple or something and if one is bad then mostly all are bad. I had never had a problem before this week. The house is 2 years old. So I said if it's a staple or something, wouldn't changing the room fix that if it didn't have an issue with "leaking?" I then asked him to check two other cables. They all failed as well. So I told him that it is very unlikely that 3 out of 3 cables had staples or something in it. He said he would just re run a new coax to the room I wanted the internet. I asked him why running one coax would fix it if one is bad then all are bad? How does he know which one is bad if he can't tell me which one has the "staple" in it? Wouldn't there still be a problem? Is there BS spewing from him? What can I do to check these cables? I also run my DirecTV through some of those cables that were checked and there is no pixelation or degradation of picture.

tl:dr

Slow internet speeds
Tech said there was "leakage"
I called BS on staple
He said to run a new coax and all the cable is probably bad