buffers dropped by pvrvideosink

Tested on pandaboard OMAP4430

pvr-omap is 41.9.0.7.1.5-2
linux-ti-omap4 is 3.4.0.1489
linux-image-ti-omap4 is 3.4.0.1489
ubuntu-omap4-extras is 1:1.6+4

I have problems playing the "hd_dts_paint_symphony.m2ts" from:
http://www.demo-world.eu/trailers/redirect-high-definition.php?file=hd_dts_paint_symphony.rar&pic=hd_dts_paint_symphony.jpg

# gst-launch playbin2 uri=file:///media/hd_dts_paint_symphony.m2ts video-sink="pvrvideosink" audio-sink="alsasink device=hw:1,0"
[... at about 5sec playtime I get...]
WARNING: from element /GstPlayBin2:playbin20/GstPlaySink:playsink0/GstBin:vbin/GstBin:bin0/GstPVRVideoSink:pvrvideosink0: A lot of buffers are being dropped.
Additional debug info:
gstbasesink.c(2875): gst_base_sink_is_too_late (): /GstPlayBin2:playbin20/GstPlaySink:playsink0/GstBin:vbin/GstBin:bin0/GstPVRVideoSink:pvrvideosink0:
There may be a timestamping problem, or this computer is too slow.
[...another 10-20 "buffers dropped" cut out...]

The "big_buck_bunny_1080p_MPEG4_MP3_25fps_7600K.AVI" & "hd_thx_terminator_2.m2ts" demo files runs without problems.

So I don't get the point actually where my problem could be.

--Roland