Hey There, I think i have a solution to your problem.  Clicking the left mouse button on your tuner knobs will lower the frequency, while right clicking will increase the frequency.  If I understood your question correctly, this should solve your issue.... I hope it does.  As for NO TECH SUPPORT, that just simply means we cannot fix any bugs or errors in the game, we can merely help you learn to fly this great bird.... as i hope i just did.