For me its headphones unless I like what is playing in the shop (we have speakers in FAI connected to the shop speakers with our own volume control. I like hard rock/metal (Disturbed, Korn, Volbeat, Slipknot, ect...)
Been going through my early 80's metal collection. WASP "The Last Command" is a gem. Juvenile metal lyrics and smoking riffs. It'll bring a smile to your face if you need one
If you like that you should watch "Steel Panther" on YouTube (at home, no kids!)