I have recently bought a bike with an Alfine 8 hub and it was working well for the first week or so. Then there was a couple of gear drop outs whilst I was riding so I made sure to line up the yellow lines at the back.
Since then I've experienced a horrible noise coming from the lowest (easiest) gear whenever I put any reasonable weight on it. If I use it on a perfectly flat surface and peddle slowly then it's quiet but as soon as I try to pedal with any speed the hub starts making this grinding/crunching sound.
Moving the lines slightly OUT of alignment actually reduces the noise but causes problems with other gears.
Should I be sending this hub back to Shimano?
I've attached an image of my yellow lines lined up.