Me and a mate are not the greatest players but we hold are own and usually get 30-40 of the kills out of 75 in HC TDM with the most we have ever got being 53. Our K/D's are 1.36 and 1.75

We both run and gun and run very similar classes (just the guns and specialist perks change as we complete challenges)

Our basic setup is

Any gun usually a sub depending on challenges

Slight of hand pro

Assassin pro

Sitrep pro

ML320 for getting campers

Frag

Flash bangs

This was up until about 2 weeks ago. All of a sudden as if it was over night  we were crap. Still finishing top but with only 20-30 kills between us and rarely going positive.

That was until my mate worked it out last night. Sound Whoring

We are guilty of it but when we do it we are running round and it just gives you a split second more to react when you can hear them coming. But as if order night the camping and whoring in HC TDM as gone mental. I can't believe it took us this long to work it out.

We changed our classes to have dead silence and sit rep after 2 kills and bang back to having our 40+ kills per match and a lot less kills

If you have found this issue maybe this could be the solution for you

Hope it helps