https://www.tnt-audio.com/ampli/vse_fvp5a_e.html 
 
"Unit has fault (noise) when RCA output is used ; Balanced output is fine ; If required, in future this model can be upgraded / repaired / rebuilt by Joe Rasmussen (Custom Analogue) in Sydney.

Its updated version is RTP3D (US$25k) - https://www.positive-feedback.com/Issue26/preamps.htm"
"Links - https://soundmovements.co.uk/diyaudio/RTP3.html
https://www.tnt-audio.com/ampli/vse_fvp5a_e.html