Listening to music: Effective or a performance hit?

I would concentrate on performance you can measure. Are team members hitting their deadlines? Does their code work and stand up to review? Are inappropriate lyrics showing up in their code comments?

If music is the root of a problem, such as the volume disturbing other employees, the employee not answering critical phone calls, or interrupting other employees to play a song, I would be comfortable bringing it up. Otherwise, I would concentrate on their performance and on behavior that I could directly link to their performance.

In any development shop I've worked with, restricting music on headphones without a clear link to existing performance and behavior would be regarded as overcontrolling and intrusive.
 
 

Hi,
I'd challenge the assumption that listening to music diminishes performance. Speaking personally, while I find listening to other people's music hugely distracting, at times listening to my own music allows me to work far more productively. 
I've also worked in teams where the agreed norm was "if I've got headphones on, I'm concentrating, please don't disturb me". Some people would even use headphones without actually playing music, just to indicate this. Given that even a quick interruption in the middle of a task requiring concentration can be very disruptive, this was a healthy habit.
A quick search on google brings up the likes of http://www.scribd.com/doc/13442043/The-Effect-of-Music-on-Work-Perfomance. This indicates that listening to music is helpful for software development. I haven't read enough to know whether this study is representative of others out there, but I'd certainly say it's enough not to ban music in already productive environment. 
Happy listening,
S.

JMCKinney has it right. To me, when an individual listens to music and is making their deadlines while not negatively affecting the work performance of others then the individual is on safe ground.
As JMC indicates, when negative behaviors such as missing phone calls, disturbing others, and missing deadlines then you can start with feedback. Other than the head bobbing, what behaviors are you observing that lead you believe that music is the cause of the performance problem? If the employee is choosing to listen to a song on the radio rather than completing a conversation...that is bad.

The use of headphones seems to be related to the industry you work in. Very rarely is it acceptable at manager level outside the manual or IT tech industry in my experience - does anyone know different?  If can be hard to work effectively in an open plan office where there is a lot of background noise. Disciple helps but cannot easily deal with the in-promtu meeting at the next desk when your deadline is in half an hour.
As an aside there is also a health and safety issue if the music is loud enough to blank out modern alarms.
Chris

In general, listening to music helps some people and hurts others. If there were loud conversations going on nearby, I would pop on my headphones to drown it out and let me concentrate. I carefully pick music that I tune out very quickly, but it blocks thing I can't tune out as easily. Since stepping into the managerial role I have stopped doing that, if only because that loud conversation is too likely to be important to me!
The most I would do, either if I notice a performance issue or as part of a general effectiveness conversation, is suggest they notice what distracts them during the day. Make them aware that the music might be impacting them, and get them to think about it. They will know whether they tune out the music to do work, or if they are tuning out the work to listen to music.
Of course, if listening to music is frowned on within your organization or by higher-ups, you also want your team to be aware that they are sending a bad message by wearing headphones during work hours.
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Chris
 
 

What about the environment the team works in? Would you have customers walking past on the way to a meeting room? I've written some code, nothing recently, with music on in the office before. No customers have access to the building and never will. The music really does help *me* (makes it more enjoyable) but it is a different story with the other types of computer work I do at the minute.
One question: If a 'big' boss came down to walk the floor what would happen to those headphones? ---
I recently visited one of our companies data centres which includes office floors with a view to relocate my team there. As I walked on to one of the floors to view the potential space a number of people had headphones in while working.
I have to admit - It gave me a negative first impression of the team working on the floor. I wont be wearing headphones in the office again for this very reason. I keep remembering this: What impression does your behaviour send to other people?