Q: 10.10.5 = Broken HDMI output (Macbook Pro 2011)
Just upgraded this morning and noticed some strange HDMI issues.
1. My 2nd Monitor when using HDMI (Asus MX279) initially had constant flickering and after re-booting/PRAM no longer works. Note that the monitor is shown as being connected and working in "System Preferences > Displays" but the monitor claims to have no signal.
2. A TV (2-year old Samsung) that I use for training would only work with screen mirroring and a 420p resolution. Used a few months ago and was fine at HD resolution before the update.
3. My main home TV (1-year old Samsung) now only displays a stable signal if set to 720p. Since the update any higher resolution and snow/static/lines show up.
Things I have tried:
I have 3 different HDMI cable options:
a) A Thunderbolt (MiniDisplay) to HDMI (my standard cable for my 2nd monitor)
b) A HTMI to Thunderbolt (MiniDisplay) converter with a cheap 1m HDMI cable
c) The same adaptor but with a longer 2m cable that came with my Xbox
None of these cables work properly with either my 2nd monitor (Asus) or my home TV. This doesn't appear to be a hardware/cable issue as things worked fine before.
I also have a VGA adaptor that I use for my projector, currently I'm using this on my 2nd Monitor (Asus) and it works fine - however any HDMI output from my Macbook since the recent update fails. So VGA = fine, HDMI = broken.
The monitor is fine, it works fine with my old Desktop PC (DVI to HDMI) and when I plugin my Chromebook via HDMI.
I've scoured the web for help, tried PRAM updates, reboots, shutdowns, safe boots etc, also tried the SwitchResX app, didn't work.
Any ideas? What I'd really like is to get back to using HDMI again. VGA isn't always available when I'm doing training sessions and I'd like to be able to run 1080p rather then 720p on my TV.
MacBook Pro, OS X Yosemite (10.10.5), 2011 model (8,1)
Posted on Sep 22, 2015 5:17 PM