Connected a Roku Express to a Dell computer monitor that has an optional soundbar attachment. Video works great and is perfect. The soundbar has to connect to a source via USB to get audio (would normally be a computer) but of course there is no USB port on the Roku. Can anybody think how to get audio to the USB cable on the soundbar? Thanks in advance!
I too have struggled with this. You don't mention the specific Dell sound bar you have, but I suspect they all behave similarly (AX510, AC511 AE515). I have an AC511, and here's what I've found: even when using the aux-in 3.5mm jack on the AC511 connected to the Dell (U2415) monitor's 3.5 mm audio output (which passes HDMI audio from a Roku), the AC511 will not play the audio from aux-in. It would appear that the AC511 sound bar still requires a USB upstream data connection to a computer in order to play the sound from aux-in. This is of course completely unacceptable, but at this time, we have no workaround. There is also no mention of this in the Dell soundbar user manual. I refer you to this Dell community link for background.
I tested each and every component so I'm confident there were no "broken parts": the monitor aux-out works with a pair of "dumb speakers". The AC511 plays computer audio when connected via USB to my computer. It also works with the aux-in audio when connected via USB to my computer. The AC511 does not play aux-in audio when connected to USB power via outlet (not a computer).
I'm posting this here as I didn't see this Dell sound bar limitation anywhere else on the Internet, and don't want people to waste their time.
(For the record, my "solution" is to buy a monitor with built-in speakers; another would be to buy a sound bar without this ridiculous limitation. Best of luck.)
Oddly enough, this was not the case for me. I stumbled across this post after trying to figure out a similar solution and almost returned the Del AC511M without trying it after reading this. Luckily I didn’t!
I have the Dell P2417H monitor, so the AC511M sound bar seemed like the perfect solution for me since it mounts right on flush.
When it first arrived, I connected it straight to the monitor and tried playing through the aux-in and originally experienced the same issue as you — no sound.
Then I connected the speaker to a Windows 10 computer and it went ahead and automatically installed the drivers for it and was playing audio fine using the computer as its source. Tried the aux-in again (while still connected to the computer) and, exactly as you mentioned, it worked perfectly fine.
Then I thought, “I wonder if maybe this connection to the computer unlocked something on the firmware/hardware side?” and decided to give it another go plugged directly into the monitor and… voilà! It started playing sound through the aux-in!
Like you, decided to post my success here so that others could give it a go if they’re struggling with the same solution.