Emergency Brake Light Blinking and Beeping

[JoRosBeetle]

Hey Everyone! Long time reader, first time poster.

I have a '99 new beetle, 2.0 litre, lots of miles but still in decent shape. Recently I've had a problem with the emergency brake light flashing and beeping (three times) when I'm idling and have a lot of power sucking devices running (rear defrost, fans etc).

It only happens when I have everything running at once and it never happens when the car is actually in motion. If pull away or if I turn off some of the things I have running, the flashing and beeping will stop.

I'm assuming the car is trying to tell me that it doesn't have enough power to run everything while idling, but I recently had the transmission replaced and a new battery installed, so power shouldn't be an issue. Also, this problem was happening before I had that work done, so it's not like the mechanic messed something up to cause this situation.

Any thoughts?

Extras Notes:
By the "Emergency Brake Light", I mean the one that comes on when the brake lever is pulled. The red one with the exclamation mark in it.

I know there are quite a few threads about this type of problem already, but there don't seem to be any resolutions to the issues in those threads. There are a lot of mentions of faulty brake relays, or driving with the emerg. brake on but those just don't make sense for my situation.