Eliminating the chain tensioner, I believe one of three things could be your issue….
1. Too large a gap between rocker and push rod.
2. Too large an end gap on the rocker assembly. I’ve had this issue. Usually heard when engine is warm.
3. If you have a multi-piece push rod, an end may have become loose which means a replacement with the newer style one-piece units.
If you need a referral, one can be provided. 🙂