I suspect your problem may be in the tuner, but FWIW....
Some stations broadcast stronger signals than others but the signals may still be pegged on the signal meter in your tuner. So prior to your problem they were all sufficiently high to max out your tuner's needs, now you are seeing the differences in the different signal strengths.
Other possibilities to consider. The fading stations themselves may have reduced their power output. That happened to me a few years ago and my favorite station is now good (noise free) only in mono. Another possibility is that the stations broadcast antenna may have been relocated to a place more distant from your house.
BTW I have a little Tivoli on my desk (mono) and it is amazing how it pulls in the weak signals. Compared to other desk top radios anyway.
Also, if the signal is weak, but otherwise clean, you might for some reason have some problems with cable and or connections/connectors on your antenna. Especially the outdoor connections. Check them out to make sure you don't have rusted wires etc. The more I think about it, the more this possibility appeals to me.
Also, on occasions I have used a 10db amp placed near the antenna and got good results by simply boosting signal strength.
Hope that helps you a bit.
Some stations broadcast stronger signals than others but the signals may still be pegged on the signal meter in your tuner. So prior to your problem they were all sufficiently high to max out your tuner's needs, now you are seeing the differences in the different signal strengths.
Other possibilities to consider. The fading stations themselves may have reduced their power output. That happened to me a few years ago and my favorite station is now good (noise free) only in mono. Another possibility is that the stations broadcast antenna may have been relocated to a place more distant from your house.
BTW I have a little Tivoli on my desk (mono) and it is amazing how it pulls in the weak signals. Compared to other desk top radios anyway.
Also, if the signal is weak, but otherwise clean, you might for some reason have some problems with cable and or connections/connectors on your antenna. Especially the outdoor connections. Check them out to make sure you don't have rusted wires etc. The more I think about it, the more this possibility appeals to me.
Also, on occasions I have used a 10db amp placed near the antenna and got good results by simply boosting signal strength.
Hope that helps you a bit.