this is a universal issue that's been around for about 2 years now. There are workarounds on streaming devices, but it's a disaster on Roku TVs - since pretty much everyone investing in a 4K smart TV will be using an external sound device and not the 10 watt built in speakers. It's mindboggling that Roku hasn't fixed this, while pushing numerous brands of Roku TVs onto unsuspecting customers.
Basically sound output from Roku TV to ANY sound device (AV receiver, soundbar, anything) via HDMI ARC or SPDIF (optical) will result in this 150ms delay. The sync problems are even worse with DTS passthrough, at 500ms and higher thus unwatchable. there is no workaround. if you enable both built-in speakers and external, you can hear the echo and menu navigation double-clicks.
All these issues go away if you plug in your streaming device directly into AV receiver / soundbar. it's like that yo dawg meme, you have to plug your roku into your roku.
to summarize, anything plugged directly into the TV (or the built in Roku) then output to external speakers via ARC or optical will be delayed.
I solved this by completely ignoring the built in Roku of my Roku TV and.... buying a streaming Roku to plug into my receiver. sync (including DTS) is perfect that way, at least for now. like i mentioned, there's been like a dozen different sync issues introduced by various firmware updates, so I'm expecting more in the future.
Buying a Roku TV was a tremendous mistake.
I'm going to talk to my Costco friends in corporate. I'm yalso going to write the board of directors and the CEO and let them know this is a terrible product to carry.
I'll wait a bit until I get some tech support to see if this truly is not fixable.
Can someone from Roku get back to me?
I want to echo everyone else in here that I too am having this problem. I have a 55R615, and a Vizio SB3651-E6. I have been dealing with this from day 1.
This happens with all streaming audio, I don't use anything else (blueray/dvd). I use Plex and Netflix mainly. Thought it was Plex, wasn't. Thought it was the soundbar, wasn't. It is clearly the TV, and Roku needs to fix this problem, it is clear it is their fault.
I don't want to deal with the customer support, as it is clear they have done NOTHING for everyone else in here. It isn't one off as Tanner likes saying. It isn't because your setup, your streaming service, or anything else you are doing. It's the Roku, and it needs to be fixed.
Roku fix this problem. I want to join the momentum for class action.