3+ years ago, I heard something similar on the Univ of Twente WebSDR:
http://www.hfunderground.com/board/index.php/topic,10205.0.htmlHaven't thought about it until you posted (oddly, I thought I heard it last summer, not 3.25 years ago).
0156Z 45444 S9 Bird calls with a cuckoo going strong. I vividly remember the cuckoo from the previous time I heard them.
0207Z Dropped from around -70 dBm to right into the noise (-90dBm). Weak carrier visible and no audio is heard. Station is gone for tonight.
While listening on the U Twente's WebSDR, also listening for a carrier on my radio, but never heard anything.