Package: gqrx-sdr Version: 2.14.6-1 I noticed that gqrx-sdr build-depends on gr-iio (which FTBFS in testing/unstable and is built against an old version of gnuradio), but there is no corresponding runtime dependency and the only mentions of iio in the build log are the installation of build-dependencies and the generation of the buildinfo file.
I did a test build with the build-dependency on gr-iio removed and it built successfully. So it looks to me like this build-dependency should just be removed.