Can anyone identify this?

["davimon100" davimon100]

Anyone good at identifying rattlers, snorers or purrers?

I recorded what is most likely an insect, but possibly a snoring troll, in a 
patch of grass beside a damp ditch, on a recent trip to Sweden.  Can anyone 
identify it?  We had a look around but couldn't find any likely suspects.  
Whatever they are they can hide in 20cm grass. 

It can be heard faintly to the unamplifed ear.  This recording was made with a 
Telinga Pro-7 parabolic about 1metre above the grass. The track is a composite 
of a few takes, but I have left it obvious where one track ends and the next 
begins. 

I later heard the same noise from a similar a grassy-boggy area, so it is 
obviously the day for it.

Details of the location are in SoundCloud (click on the 'Mystery 'insect' - 
Baltic coast, Sweden' header).

http://snd.sc/LjzXMN

Thanks,


David