I have the EXACT same symptoms as those described by @Daniel_Hernandez in the original post, including the exact same sound (thanks for the vid). I did all the same stuff and it didn’t help - replaced the BB, lubed the chain, cleaned the chainring, checked pedals, cassette, front and rear deraileurs… (I think there are a bunch of posts here addressing similar but not identical symptoms…) Appeared when I swapped my worn chain for a new one. I think the issue is the chain sticking in the cogs on the small ring. The sound seems to come from the chain pulling away from the cogs. The chain visibly vibrates as it pulls away in time with the sound. (No vibration or sound on the big ring.) I believe it only appears when I apply power because the power causes the chain to wedge tighter into the cogs. Possible that there is wear on the inner ring from cycling too long with my worn old chain. (I don’t get why wear on the cogs would cause the sticking: seems like wear on the cogs would make them release the chain more easily. But in a weight weenies forum, people seem to think it’s the wear that is causing the sticking. Chain/chainring noise with new SRAM Red AXS 12s chain - Weight Weenies) This would also explain the sound diminishing over time as the new chain wears in, as Daniel describes. I think SRAM should take a look at their manufacturing - feels like BS that I have to replace the chainring set ($$$) because I rode a couple thousand miles on a worn chain. I get chain wear, but the chain rings should be more durable. Of course, maybe they like it this way…