Grasshopper Warbler

Not the finest photograph I've ever taken! It is a very boring-looking bird and the image is cropped to within an inch of its life....but it's a lifer for me :)
Locustella naevia
I decided to return to Levenhall Links, after being there a week ago. Very few birds in comparison, though still a few blackcaps and willow warblers.
I could hardly believe my ears when I heard the call of this wee fellow...it's a bit like an old-fashioned alarm-clock with the bells muffled (or, in fact, a grasshopper's chirp!). Went on for 10 or 15 seconds non-stop. I spotted the bird in a bush, as I moved round to get a photo he scuttled downwards into the grass and skulked about.