Buy new or repair? Budget $600 ish, existing Nakamichi RE-1

I have two hi-fis; one in my main room that isn’t used much (Fisher Philharmonic 280 chassis using the original receivers turntable jury rigged to an H/V 440VXi/Nakamichi BX-2/Nakamichi OMS-1A that is a little tempermental) that absolutely suits my needs, and the one I have in my entertainment room that is used quite frequently.

It has a Nakamichi RE-1 hooked up to a Nakamichi BX-2 that works good, a JVC 6CD/Single unit whose model name I don’t quite remember (I don’t usually play CDs much anyway) and a Audio-Technica LP120USBX or whatever the current model is. It is driving a pair of Yamaha bookshelf speakers and it sounds pretty good when it’s working. I use the video function using a 2-1 splitter to accomodate either input from a TV with RCA sound outputs or to send sound from my computer using a DAC. I use the tape record function via a similar 2-1 splitter to either record sound through to my tape deck or to send sound from the cassette deck or record play ro my computer for digitization purposes.

It serves three primary functions: digitizing cassettes/records, improving sound for the TV, and handling the sound output of the computer. I absolutely need a line-out unmodulated RCA pair to send sound to the computer, and I would ideally prefer two so that I can send to both the tape deck and the computer, particular computer DAC to tape deck. 

As I said I really like the way the Nakamichi RE-1 powers the Yamahas and I like the fact that it has plenty of power in reserve so that I can eventually go with bigger speakers when I redo the room and move the system so that the speakers aren’t firing at the party wall between my house and my neighbors. The issue is that the A speaker output is frequently choppy on the left channel, and the B channel is iffy on the right channel, so that I have the left speaker hooked to B and the right speaker hooked to A, and sometimes when I turn the system on the left speaker will not fire, and I will need to crank the volume briefly to wake it up. 

As a general rule I prefer a generally neutral sound because I listen to a wide range of music, concentrating in early Jazz, very early R&B (think Wynonie Harris), and particularly Doo-Wop, but also running to stuff as early as the Dimwiddie Colored Quartette and as recent as the mid-2010s, and I really prefer it not to be too particularly colored by my equipment. And as I said, when it is working properly, I really like the way the RE-1 handles everything I throw at it, but I am a little tired of the problems- and I assume they will only get worse.

I find myself torn between either somehow attempting to get somebody to fix whatever is wrong with the Nakamichi RE-1 or replacing it with a newer system. My wife is… patient with my music hobby’s cost, but I don’t want to go higher than $600ish, and can’t afford to spend more than a grand at the moment. I was considering the Cambridge Audio AXR100 as an alternate, but I would be open to other neutral sounding systems at or below $1k, but if the sound IS colored, I think I would prefer a brighter sound to a darker one, so not the Marantz NR1200 for example.

All advice greatly appreciated. If I sound like I’m trying to be knowledgeable, it isn’t intentional. I started this hobby a couple of years ago and know very little.