42v to +/-24 DC-DC isolated buck-boost converter 10A

Hello Everyone,

I have 3 car batteries in series in order to power my amplifier. They are charged with a simple linear PSU. For many days I am trying to find a controller that I could drive my buck-boost circuit with and keep the output voltage stable. I have been through many dozens of products of many manufacturers but I just can't seem to be able to find what I need.

Did any of you stumble upon an IC that could do the job?

Many thanks in advance.