I used to play piano when I was young. We had a poodle who when sitting with me on the piano bench, would howl just like that when I played. But only when he was on the bench with me, not when in another room. Strange.
I had a dog years ago, a mutt adopted from the Humane Society that would howl when I sang “On Top Of Old Smokey.
LOL
Neighbor kids would come by and ask if they could hear the dog sing.
Life was so simple then.