Audio Systems: pioneer home stereo receiver, home stereo receivers, audio circuits

Question
I have two Pioneer home stereo receivers (sx-1700, vsx 402). They are old but quite spectacular when working properly. The SX is beginning to have problems with the tuner/radio function. The sound will kick out and come back with no predictability. No issues with the other modes such as cd. The VSX no longer has sound separation. By way of example, with just one speaker hooked up it produces sound with the balance turned from one extreme to the other. In the past when it was hooked up to be say the right, when balance was turned to the left no sound would emit. Thanks in advance for your time and thoughts on this.

Answer
The SX kicking out on radio may be related to the antenna, cars going by, etc.  Try changing the antenna or input connections to see if clears up.

Some times the "mono" switch gets activated; check that out.  Otherwise the VSX likely needs service by an audio tech who can get into the audio circuits and test out the functionality.

Let me know if you need more.