Volume controls behave incorrectly when connected to LG UltraFine USB-C monitors

Originator:andy
Number:rdar://30114548 Date Originated:2017-01-20
Status:Open Resolved:
Product:macOS Product Version:10.12.2
Classification: Reproducible:Yes
 
When connected to an LG UltraFine series (4 or 5K version) monitor, volume step-changes are too significant in comparison to any other form of audio output.

The first 2 bars represent a huge difference in audible volume compared to the output of headphones, speakers, BlueTooth earpieces etc. making the key controls unusable.

Steps to Reproduce:
1. Connect a late 2016 MacBook Pro to an LG UltraFine 4K or 5K monitor.
2. Play some audio.
3. Use the keyboard volume controls or drag the TouchBar control the alter the volume.

Expected Results:
Gradual increase/descrease in volume similar to those experienced via other connected audio devices.

Actual Results:
Significant changes in volume going from very quiet to very loud within 1-2 clicks of visual scale. The top volume is far too loud for any environment and distorts terribly.

Version:
10.12.2

Notes:
This issue was reported initially to LG who accepted no responsibility. I've seen been through Apple Support and to an Apple Store where the situation was replayed with different MacBook and LG display configurations, all with the same outcome. No one is sure if this is a hardware, monitor/MacBook firmware, or macOS issue.

Configuration:
MacBook Pro (13-inch, Late 2016, Four Thunderbolt 3 Ports)
LG UltraFine 4K Display
macOS Sierra 10.12.2

Comments

Same issue. Really hope this gets fixed as it does go super loud going from headphones to the speakers and not realising the levels.

By harry at Feb. 16, 2017, 2:16 p.m. (reply...)

Exact Same Problem

I'm running a 5K with the 2016 Touch Bar MBP. This seems like it must be a software issue.

By kevin at Feb. 9, 2017, 2:29 a.m. (reply...)

Same problem here. The speakers jump up to 30% volume within the first 5% of the volume up key on my MacBook keyboard. A temporary solution I've been using is to hold Option and Shift while adjusting the volume to reach increments in between steps. I hope a software update is pushed to the display for this issue; it's very annoying.

By tbonvallet at Feb. 2, 2017, 3:17 a.m. (reply...)

Same problem here.

Volume on LG Ultrafine 5K goes from barely audible to extremely loud within 1-2 clicks of the visual scale. Doesn't seem to depend on the Macbook though. I can reproduce the problem with a really old Macbook (2012 or so) as well as with the newest Macbook Pro (late 2016). I hope it's something an OS update may eventually fix. I'd rather not have to exchange the monitor :-(

By markus.mottl at Jan. 25, 2017, 10:20 p.m. (reply...)

Here the same problem; very interested in a solution. It's almost unusable to use the volume now. Or too soft or far too loud.

By rafael at Jan. 25, 2017, 2:36 p.m. (reply...)

We are seeing the same problem.

By k at Jan. 24, 2017, 3:01 p.m. (reply...)

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