I have noticed that when I pick up a guitar, nine times out of ten I automatically assume the Am chord position. When I stand at a keyboard it allways seems to be the Cm position. Although obviously I can play in other keys lol, I must admit I seem to be drawn to the minor keys as an automatic starting position. I put this down to the fact that I am a miserable git and love music played in minor. Does anyone else find themselves automatically assuming a certain starting position on their instrument of choice and can you offer a reason why.
ooh been there done that. I used to have a friend of mine tune my guitar before i got there, just so I didn't have to hear the distracting tones.
Try singing the what you hear in your head repeatedly, then try to transcribe it.
If you can't or find yourself getting lost, try recording you humming/singing the important part of it. Melodically, you can get back to it a little easier should you become lost.
You can use the most ice age cassette recorder if that's all you have, it doesn't matter. It will save your bacon and your would be tunes.