Not specifically ML, but I am a huge fan of SoftwareEngineeringDaily, which always features really prominent and poignant guests. Among others, they have a "Greatest Hits" episode about AI: https://softwareengineeringdaily.com/2019/01/31/architects-of-intelligence-with-martin-ford/
Not found AI/ML specific ones that I like yet
I like a16Z which often has good content on the wider sector though https://a16z.com/podcasts/
It's from the VC firm run by Marc Andreessen and Ben Horowitz, so they're well connected and often have interviews with founders and other interesting AI folk.
I'm also a big fan of EconTalk, which originally was primarily an Economics podcast, but these days has interesting interviewees from across academia and business. Quite often these sessions discuss AI ethics and the social/political/economic consequences of new technologies or trends - https://www.econtalk.org/