Thanks for the reply, Apologies for the delay for some reason every time I checked the forums seemed to be having issues.
I noticed there were issues when using Rockbox mode when transferring files and tried the transfer using apples own firmware and noticed no issue so from then that's how I've been transferring my files but still seemed to get the issue. After posting in this thread I converted my entire library to 320kbps and found no issues, I then attempted some know FLAC songs which I experienced issues with and still came across the issues mentioned in my previous post.
Yesterday I came across another issue which gave me an error and prevented me from booting into Rockbox longer than 15 seconds (since forgot the error code apologies) but I ended up doing a factory restore and starting from scratch, and transferred my lossy and 320 converted FLAC files and found things to be stable once more, I once more attempted some FLACs which I experienced issues with and found these to my delightful surprise to be working!
My only assumption is there was something wrong with the formatting, to confirm however I had tried this at least 4 times prior so not exactly sure what was different this time
Just to note all this particular pose is currently Apple 5.5 with a apple 6th HDD, I must admit however it was rare I got the FLAC files to skip mid song unless it was a huge 24-96 file which by that point I thought it was just the HDD not being able to keep up (these now also seem to be working without issue however).
with all the above said, I am content to start looking into modifying my 6th gen to Micro SD cards once money allows
With regards to your silence issues, may I ask (no offense intended) are you 100% sure the buzz/hiss? is not supposed to be there?, if you are have you just for the sake of science tried converting it to ALAC and seeing if the Apple firmware plays without the his (just to help rule out the iPod over Rockbox)
Also thank you for your input on the Dev build, I may just transition over to that once I'm confident in the stability of this reformat.