Thanks for replies
I understand the color coding ok Mac, & I understand they use 3.5 mm plugs.It's just that the part you hold to plug in or out is so big on all my plugs & the sound card holes are so close to each other on every sound card I have ever owned (usually Creative)that it is difficult to get two plugs in side by side. I keep loosing stereo sound because line in is pushing sideways on line out causing a poor connection....Hank