[quote name='discreet' timestamp='1326721558' post='1500939']
An induction loop is designed to be permanently active, not least because the hotel (in this case) could be in breach of the Disability Discrimination Act (DDA) should it be switched off. Not sure what you can do about it though, sorry!
[/quote]
I don't think that DDA applies here as you are playing music at greater than 90db
You can just unplug the system as they are 'active' but if the venue's staff don't know anything about it, you are stumped!