[Discuss-gnuradio] QT Freq Sink Display not centering correctly?

[Jason Noble]

So, I first noticed this problem with my main GNURadio install (3.7.5 on Debian Jessie) but I've reproduced it on a brand new 3.7.7.1 live USB.

Basically I'm looking at two frequency sinks. One of them centered at 0 and one centered at 16kHz. I have a single signal source input to both sinks, starting at 4kHz but adjustable up to 32kHz. My expectation is that the initial 4kHz signal will display at the far left of the 16kHz-centered sink....but it doesn't. It displays as a 20kHz signal instead, to right of center.

I'm pretty sure that's not WAD...and if it is, can someone explain why?

qt-freq-signal.png
Description: PNG image

sink-display-error.grc
Description: application/gnuradio-grc