Bluetooth speaker JBL Charge 2 and MacBook Pro (Mid 2012)

Hello,

MacBook Pro (Mid 2012) finds my bluetooth speaker (JBL Charge 2) and pairs with it, but after a while the speaker is disconnected and cannot be selected as audio output. No audio whatsoever. I don't have any other bluetooth equipment connected at the same time and I'm running OS X Yosemite 10.10.5. Wonder if the problem is common among bluetooth speakers or is it just with this speaker? With my phone the connection is good.

Thanks in advance!