Hello Doug, this is Emily.
Try this instead.
Hold down Windows + R keys, then type in mmsys.cpl and hit enter.
When launched, you should see at least two playback devices listed, your line-in jack and your monitor, wording can be slightly different.
You can right click on the monitor and make it defaul device there, make sure it is default device, not default communication device. If for any reason the monitor one is grayed out, right click and enable it first.