I’ve got quite the issue that I’ve been trying to track down for weeks. Recently, I upgraded from an old PC to a newer one. One of the things to go was the dedicated PCI sound card (new computer’s mobo only had PCIe slots, side note: Do y’all recommend a dedicated sound card?). On that old PC, I successfully was able to record from line-in receiving input from both L and R channels. Fast forward to the new desktop: plugging the line-in in the mobo’s built in line-in port produced input from only one channel. I was thinking that maybe this was a cheap mobo issue, so I went out and bought a cheap USB ‘sound card’ that had a line-in on it. I go to plug the line-in and loo and behold I’m only getting input from the right channel, just like before. Great. Being the inexperienced audio guy I am, I decided to try out purchasing some 3.5mm stereo female to 3.5mm male mono adapters. With or without this little gadget that cost me under 5$ off ebay, I’m still only getting the right channel from both the on-board and USB line-in recording.
One thing that was weird about the original setup was that there was a mono, cable plugged into the black 5.1 port, and a green stereo cable plugged into the the green port (of course, the line in was plugged into the line in port). The on board audio isn’t 5.1, so I couldn’t mirror the previous setup but the USB one was 5.1, and even after plugging things in precisely how they were plugged in before, I only get the right channel. Is this a mobo issue? Bad coincidence? Incompetence?