Victory Disc by Andrew Cartmel

The third book in the hilarious and enthralling Vinyl Detective mystery series. "Like an old 45rpm record, this book crackles with brilliance." David Quantick on Written in Dead Wax
When one of his cats accidentally discovers a rare Victory Disc, the Vinyl Detective and his girlfriend Nevada are whisked into the world of big band swing music, and a mystery that began during the Second World War.
Hired to track down the rest of the highly sought-after recordings of the Flare Path Orchestra, our hero will discover that the battles of the last world war aren't over yet. And if all this sounds simple, it's only because we haven't mentioned drive-by shootings, murderous neo-Nazis, or that slight case of being buried alive...