Update on last nights post. All was fine for the first hour, sound changed over the listening period with vocals defintely fleshing out more as time went on. That was until i started getting artefacts, especially on high dynamic swings, notably drum impacts and bass.
I played around with the I2S settings again, sometimes it would clear but not always. Checked cable connections, rebooted just about everything i could think of including the SoTM SMS200 Ultra (used as HQPlayer NAA, fixed volume with -3db, Sinc-M, LNS15 and 176.4K PCM - nothing too severe) and Antipodes CX. Again all was fine for a bit then artefacts returned. The only other item in the chain is an Audioquest Vodka HDMI 48K cable, all components the same as pre FPGA upgrade.
Mixed feelings when i ended the session, sound (when working) was damn close to what i would expect going from the Venus to Terminator, it was that good. Just need to bottom out the source of artefacts, will raise a call with Denafrips.
Anyone else had similar issues using I2S post v3.5 on a Venus II?