Schlaboatnic

Hello, First post here so here I go. I've got a pair of Heresy ii's I bought new in 86 (I think). I have the hooked up to a Carver AVR100, also bought around the same time, so both in use for nearly 40 years (damn I feel old now). Recently the right channel side would just stop, or come in and out intermittingly. I would switch the speaker select from A to A&B and it would sometimes resolve itself. I had figured it was a Carver issue, so took it to the hi-fi shop where they tested it and could not find anything wrong. I got it home, hooked it up and soon same issue. I hooked up an old speaker to the right channel and it worked just fine, so now it looks like the Klipsch is the issue. Would replacing the crossovers be a good start to solving this issue? They have not been abused over the years and I do like the sound. Is there a easy way to test the crossover, and do they eventually fail? Thanks for any insight