Second try. make it –
sudo find / -name “*librtlsdr*”
The instruction above should get sdrglut working with your RSPDuo and if you rebuild sdrTest, it should also work.
You stick does not seem to have the direct_samp option – so you are stuck above 27MHZ-
Try your luck at fm
./sdrTest -fc 101.1e6 -f 101.5e6 -fm -gain 1 -device 1