I am also sharing from a Windows 10 PC, thus far on firmware 90G, I do not have stuttering issues. May I suggest those who are sharing off a Windows PC, to open up task manager and monitor the network traffic while playback is happening. I notice the average send bitrate ranges from 25-50Mbps depending on material being played, but sometimes I see sustained (15-30 seconds) spikes at 200Mbps. Look out for congestion or choking on the PC side. If you’ve tweaked your TCP parameters, revalidate them for LAN rather than internet (especially the congestion control/retry wait times). Check 'netstat -e' for errors. Do ensure the Windows 10 PC can respond to demands from the Z9X, and that the PC isn't overloaded with other tasks.