In 2019, Grunwald signed with Bloodlines Music, the company re-released his back catalogue on vinyl in February 2019.
In June 2019, Grunwald released "Whispering Voice" with Kasey Chambers, the lead single from Grunwald's ninth studio album Mojo. Mojo was released in August 2019 and peaked at number 40 on the ARIA Charts. Mojo was produced by Brian Brinkerhoff, Carla Olson and Ash.
Also in August 2019, Grunwald published his first book Surf by Day, Jam by Night. In the book, Grunwald interviews 15 of the world's top surfer-musicians; including Kelly Slater, Stephanie Gilmore, Jack Johnson, Dave Rastovich, Pete Murray, G. Love and many more. It was published by Pantera Press on 19 August 2019.