Thread: No right Channel for line in

Hey All,
When I plug in my XM Direct Universal Tuner into line in, I only get left channel but I can hear music(hard drive stored) or my Navigation speech on both channels. When I plug my XM Direct Universal Tuner into Microphone I hear Both channels.

What the hell am I doing wrong?
I was thinking on getting a USB DAC would that fix my problem??

Thanks