RE: XPS 13 9360 - first half-second of any sound is missing from USB-C/HDMI
Thanks for your response Jim. I'll PM Brad-L. Thanks for the pointer to him. (I'm just like everyone else; I came here only to post my own issue. These types of boards work better if there's an active company presence.)
Thanks also Saltgrass for your response. I'm not sure what you mean by Firmware; I have no external Thunderbolt device or other hardware, so the only firmware I can think of is the 9360's BIOS, which I did update to the latest. And regarding drivers, at first I updated the audio driver but it made no difference. But after a while I came to think that it's really the Intel video hardware and driver that's responsible for audio over HDMI. So I updated to the latest from the Dell website, then I forced it to install the driver from the Intel website. (I had to uninstall the Dell/Intel driver to get it to allow me to install the pure Intel driver, not from Dell.) Anyway, no improvement.
Yes, not only have I seen the problem on two output devices, but one of them is normally connected to another PC and gets its audio via HDMI. It does not have the issue when connected to this other PC.
And the beginning of every sound is missed, not just the first of a group. For example, I can click the Test button on the Sounds tab as quick as I can after each short Windows sound plays, and the beginning is upcut every time. If it's some device going into a power save mode and needing a few hundred milliseconds to wake up, it goes to sleep instantly whenever a sound stream stops.
(Your touchpad problem sounds very annoying. I hope you can get it resolved.)