Broken Nakamichi CA-7A phono


Hi,

I have just received my Nakamichi CA-7A which I bought from an ebay seller for $900. I was super excited to use it to replace my CA-5, which works great with my Rega TT (Ania MC cartridge) though it has a few issues with balance control.

While the new CA-7 works great with my CD player, Aux (Chromecast Audio), it makes a broken noise (not sure how to describe it, please see this video) as soon as I switch it to Phono input. 

https://www.dropbox.com/s/beafocypf4bawvb/VID_20200216_120837.mp4?dl=0

This is the case whether or not my turntable is attached to the phono input.

I have double checked by connecting my TT to existing my CA-5 and connecting it to CA-7 Aux1/Aux2 (of course very low gain). And, i verified that input on the rear panel is correctly configured.

I have reached out to the seller to see if he can help me out. Can anyone of help me figure out what could be going on here?

Thanks
objectivecpp
You got a bad phono stage in there. Shipping back for refund is a hassle, but will come to be seen as a lucky break once you find something better for the same or less. Good luck.
Thanks for the response. I will ask the seller to accept the item back.

Is there anyway this can be repaired or it looks behind repair? And, what do you call this noise? 
Sounds like feedback. Double check to see if your plugged into the correct input and that the switches are in the proper positions. If all is good, then I'm with mc, send it back or negotiate a partial refund to pay for the fix. I bet the seller didn't test the phono stage. 
Thanks, feedback persists even without connecting any phono input (as soon as Phono input is chosen. Every other input is good - Aux, Tape, CD)

Can it be fixed? How much will it typically cost?

Thanks!
Hard to say, techs charge between $60.00 - $90.00 just to diagnose, then the estimate. Probably worth fixing tho, that is a very flexible preamp. I certainly would contact the seller, explain the situation and see what he offers to start.
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Get your 900 bucks back and buy something new for the same amount that you spent on that 30+ year old preamp. This would fit the bill! 
https://www.audioadvisor.com/prodinfo.asp?number=PAC200PRE