Is there a LEGO podcast?
The All Us Geeks podcast regularly has a segment on LEGO called the Brick Breakdown that is run by William and Sarah Reed. Here is the link to the latest episode (scroll down to see when the Brick Breakdown section starts): http://www.allusgeeks.com/2015/08/episode-60-dead-men-tell-no-tales/

My guess is that because LEGO is so hands-on and so visual, it is kind of hard to run a fully dedicated podcast about it. William and his wife mainly talk about things like the history of LEGO, investing in LEGO, etc. That's pretty much all you can do through a podcast.