Is there any device that could enable to plug both speakers (JBL Creatures) and headphones (Sennheiser CX200) into my iMac? I use the headphones when I play games and the speakers when I watch TV shows. I wish I could avoid having to plug/unplug the audio jack into my iMac every time I make a change. I would love to have something like a switch that would let me have both the speaker and the headphones connected at all times and enable me to pick which one I want to use. Thanks.