BBM Voice Chat - battery drain

A friend and I play online games weekly. In the past we've used our PlayBooks with voice chat, and will fully charged PlayBooks we could talk 5+ hours with only minor battery drain (~30%).

A few weeks ago, my router started to dislike my PlayBook, so we tried using BBM voice chat instead. I have a Z30 and my friend has a Z10. Wow, does it ever suck juice from the battery. Even with a fully charged Z30 I need to plug it into a charger after a few hours. I should have checked the App Monitor, but it was pretty obvious that BBM was draining the battery. The display was off. I've also tried using the internal speakers and headphones and the battery drain seems to be the same.

Why would the PlayBook run voice chat like a champ, but our fairly new BB10 devices have a hard time?

Has anyone else tried having long conversations using voice chat?

Knowing the PlayBook has a capacity of 5300 mAh while the Z30 only has 2880, not surprising.

Cave, cave, moderator videt