SDR AIS available in OpenPlotter 2

[pabben]

I have a realtek dvb-t rtl2832u and it was working fine in openplotter 1.
Now i am unable to calibrate. After choosing device and clicking "inital ppm" it stops at "Allocatin 15 zero-copy buffers" and nothing more happens.
I have left all fields blank. PPM is set to 13 manually (just a random number)

***
Found 1 device(s):
0: Realtek, RTL2838UHIDIR, SN: 00000001

Using device 0: Generic RTL2832U OEM
Detached kernel driver
Found Rafael Micro R820T tuner
Supported gain values (29): 0.0 0.9 1.4 2.7 3.7 7.7 8.7 12.5 14.4 15.7 16.6 19.7 20.7 22.9 25.4 28.0 29.7 32.8 33.8 36.4 37.2 38.6 40.2 42.1 43.4 43.9 44.5 48.0 49.6
[R82XX] PLL not locked!
Sampling at 2048000 S/s.
Reporting PPM error measurement every 10 seconds...
Press ^C after a few minutes.
Reading samples in async mode...
Allocating 15 zero-copy buffers