Line out or headphone out should drive any XLR mic input to FULL TILT BOOGIE with no problem at all. You have something else FUBAR like input cables...
I think you must be right, the only thing common with all my attempts that did not inclued the 1/8" stereo to XLR(which fried the headphone amp in one of my Ipads due to Phantom power being on) was a pair of RCA to 1/4" adapters that I have.
I'm shocked no one else has experienced this phantom power frying headphone amp problem. I had never heard about it until it happened to me and then searched the net and discovered that is quite common.
I'm afraid to use the XLR inputs again because of that phantom power issue, so I opted to use the 1/4 " inputs. I had a bunch of 1/8" stereo to dual RCA cables laying around and bought a pair of RCA to 1/4 adapters since I could not find any 1/8 stereo to dual 1/4 cables locally. I did try swapping out various 1/8 stereo to RCA cable but always have been using the same 1/4 adapters.
I bet that $3.00 item is the problem. Makes sense since I never had any issues with my other board that has the RCA inputs on it.
Just ordered one of these:
http://www.amazon.com/gp/product/B005HGM1D6/ref=ox_ya_os_product_refresh_CThanks everyone for helping me think this thru and avoid buying a $169 DI that I might not need.(Well, you know I'll get one eventually just because it's a cool toy to have in the bag)