Just went from an Index to a Bigscreen Beyond. No buffering at all when using h.265 in the Index but in the Beyond it frequently pauses like what @CraveDastry had, doesn't matter the quality setting. This sites speed test had me in the LA CDN and I had 707mbps streaming and 525 parallel streaming.
Edit: DeoVR Version is whatever is the most up to date steam version in the past week is.
Edit 2: Seems to be tied to a sleep function in either DeoVR or the headset. If you hold your head still for too long DeoVR will pause until you move your head a little bit. No idea how to fix this as the range for “no movement” is kinda high