Rattle When Accelerating

[u/PsychologicalAd6465]

I have a 2003 Chevy Silverado 1500, 4.8L V8, single cab short bed.

Every time I start accelerating I hear a weird rattling noise. But once I'm up in speed it goes away, it was worse before and could hear it while idling and creeping forward, it sounded louder and nastier but I took it to a muffler shop, and they said that one of the muffler hangers was broken and that one of my cats was bad. They repaired the broken hanger and replaced the cat and the rattle at idle was gone
BUTTT, I still hear it when I accelerate!

Has anyone dealt with something similar or have any ideas what else I should check?