Just got a K5200 for my LG 27UL650 on my Windows 10 HP z840 workstation. The LG monitor is good for DP up to v 1.4 and the K5200 has two DP v 1.2 outputs. The LG has built in speakers for either DP or HDMI connection. I installed the latest Nvidia drivers including the Nvidia high definition audio driver. Under Sound settings I set to "LG 4K (NVIDIA High Def Audio)" but no sound. I saw the K5200 had a edge connector marked stereo... am I missing some connection? Any idea why no audo output?