I have one question I bought the RN800A and love it but am setting up turntable with x5 phono pre amp is it correct I should not use the existing phono inputs on amp but should use a line in instead (would this cause damage if existing phono inputs used) if so that leaves me with not enough inputs - z8 DAC with DMPA6 Streamer and cd player wanted to connect the JBS JB940 Minidisc but can't if this is the case
That is correct, that you can not use the phono input of the RN800A if you use an external preamp. That is because you will be applying RIAA correction twice and the output from a phono preamp will be far too high for a phono input. So you have to use a line input.
Your best solution is to get rid of the X5 Fosi phono preamp. In any event the phono input of the RN800A is will be as good or better to than that FOSI unit, so get rid of it, and your problem is solved. It also cuts out a cable, and your are less likely to have induced hum, which turntable connections are very prone to. So deep six the FOSI.