Need Help JV3 colour profiles question

Hello everyone we manage to pick up a second hand JV3 160SP that is in mint condition and works flawlessly, it had been used as a back up printer, for years and had been serviced regular and honestly looks and sounds brand new, i couldnt turn it down at £750.

Anyways this SP came with dual CMYK setup and we have had it printing fine but the odd colour and especially when printing black to grey fades and solid black, we always eem to get a muddy dark brown, we run this on flexi rip subscription, and the guys there tried through teamviewer to install some newer profiles from the mimaki website, to try and get a better looking print but the dither was off and even though th eblacks were oming out a lot better the print was grainy. they now suggest having a printer profile made to get it right.

is there anyone on here with any custom profiles made for the JV3 or could tell me how to go about creating one, or any help and advice please as regards this, i know i may be asking a lot as its a very old machine (2005) but it seems a shame to not get it right and get a few more years out of it as i cant afford a new shiny one.

tia

Alan