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msjgau
Jan 6, 2011, 09:57 PM
OK! I bought a mini Display port adapter to DVI-D and a DVI -D to HDMI which is plugged in and works perfectly (after an hour of searching and finding all I had to do was click the Mirror Display) but no audio obviously. I also bought a 3.5 mm cable which was recommended by the sales person. I put it in the headphone jack and have tried 2 of the available audio jacks on the back of the tv. The tv is an LG LED LCD The model number is 32LE5300.

Any input would be much appreciated!



dtaylor
Jan 7, 2011, 08:51 AM
Do you have a optical input on your tv?

This is how I do it...

I have a DVI to HDMI cable that I plug directly into my tv. I set my mb pro to wake on bluetooth. So I have the laptop turned on and plug it into the TV. I then close the lid causing the laptop to go to sleep. Next I wiggle my bluetooth mouse or hit a key on my bluetooth keyboard and it wakes up the laptop with the tv as the primary and only display. I believe you can use a wired mouse/keyboard to wake it up as well. Once the TV is the main display, you can open up the laptop and the laptop display will stay off and you can use the keyboard/trackpad.

Audio:

I use a toslink cable (http://en.wikipedia.org/wiki/TOSLINK) with the 3.5mm plug like thing adapter on the end. You just plug it into the audio out jack and into a receiver or tv. With that, you can have surround sound or stereo depending on what you are plugging the audio into.

I hope that helps a little.

mchalebk
Jan 7, 2011, 08:51 AM
Your TV is probably expecting audio to come in via HDMI. I don't know if you can combine video from HDMI with audio form another input. However, I think the following will do everything you need:

http://www.monoprice.com/products/product.asp?c_id=104&cp_id=10428&cs_id=1042802&p_id=6331&seq=1&format=2

toneloco2881
Jan 7, 2011, 10:26 AM
How new is your MacBook Pro? If it's the one introduced in April of '10 or later, you can output audio through the DisplayPort as well as video. You would need this type of adapter in order to receive audio through the DisplayPort:

http://www.griffintechnology.com/products/video-display-converter

If it's an older Macbook pro then the adapter suggested by a previous poster will work for you. That adapter allows the audio to be transferred by USB, which is then fed into the converter, and passed along through a single HDMI cable into your television.

The problem is most televisions don't allow a separate audio input while utilizing an HDMI connection, as its expecting it to be fed through that single cable. Another option is to just run analog or digital audio to a receiver if you have one of those in proximity to your television, and connected to external speakers.

Lastly, are you sure you want to just enable mirroring to your external display? I looked up your television, and it appears to be a 1080p model, and unless you have a 17" MacBook Pro your screen is running at 1680x1050 max, which is not supporting the full resolution of your tv. Sure, its a 32" so you won't notice much of a difference, but all things being equal it's best to output at the 'native' resolution of your TV; especially with fixed pixel displays. What I would do is enable extended desktop, and choose to output at 1920x1080 or '1080p'.

mchalebk
Jan 7, 2011, 12:38 PM
If it's an older Macbook pro then the adapter suggested by a previous poster will work for you. That adapter allows the audio to be transferred by USB, which is then fed into the converter, and passed along through a single HDMI cable into your television.

Actually, the USB connection is only for power. The audio is passed using the optical output of the MBP into the adapter. From the monoprice website:

This adapter connects to a female mini displayport to provide video, a USB output to provide power, and includes a mini toslink to toslink cable to connect from the 3.5mm (1/8 inch) digital audio output of your compatible Mac to the toslink input on the adapter in order to deliver true digital audio and video output to the adapter's female HDMI port.

toneloco2881
Jan 7, 2011, 04:03 PM
Actually, the USB connection is only for power. The audio is passed using the optical output of the MBP into the adapter. From the monoprice website:

I stand corrected. I have the one with just a USB connection for audio, and wasn't aware that there is now one with a true digital connection available. I should have read the description instead of just looking at the picture ;)

Thanks!

msjgau
Jan 7, 2011, 07:09 PM
My suspicions were proved right. I had a feeling that the HDMI wouldn't allow a second audio line.
I'm going to seek help from a friend or order the monoprix adapter. I'll also go back to Futureshop with my new found info and let the sales guy know he was wrong.
Thank you very much!

waw74
Jan 7, 2011, 08:02 PM
how old is your mac?
if your mac does support audio out over the Mini display port, audio might work over DVI. I have the new mac mini, with mini-display to DVI, then a DVI to HDMI cable. and i can get audio on the tv over that cable.

go into system preferences -> sound -> output, then click on "LG TV" (probably, that's what mine says, have a different model though)

And yes i know, DVI doesn't carry audio, but someone forgot to tell my tv that, because it works.

ftaok
Jan 8, 2011, 10:11 AM
msjgau,

I'm looking at the spec sheet for your TV. The rear connection panel shows an audio input (3.5mm minijack) that is labeled for RGB and DVI. The HDMI inputs are labeled HDMI/DVI In.

I'm guessing that at least one of the HDMI inputs allows for auxillary audio to be used. My guess would be HDMI 1 is also the "DVI" port.

Not sure about LG's, but my Sharp allows aux audio for HDMI4, but I have to toggle it to accept the aux audio in the menu.

Have you tried that? If all else fails, consult the manual. I'd be willing to bet that this will work without buying an expensive USB/HDMI adapter. Of course, if you just want to run one cable from the MBP to the TV, then you will need that adapter.

EDIT - I just read the manual for your TV. The salesperson was right. HDMI-1 serves as the DVI port and as such, can accept the audio using the RBG/DVI Audio In. Take a look at your manual ... page 46 will show you how to connect your computer. Funny though, there's no mention of needing to go into the menu system to select the aux audio input ... but you know how these manual translations go.

ftaok
Jan 8, 2011, 10:21 AM
how old is your mac?
if your mac does support audio out over the Mini display port, audio might work over DVI. I have the new mac mini, with mini-display to DVI, then a DVI to HDMI cable. and i can get audio on the tv over that cable.

And yes i know, DVI doesn't carry audio, but someone forgot to tell my tv that, because it works.

Are you sure? Because that really shouldn't work. The audio would get dropped at the DVI connection points because the "pins" for audio isn't there.

Also, since you have the new mini, why don't you just use the HDMI port and a standard HDMI cable?

waw74
Jan 8, 2011, 01:29 PM
Are you sure? Because that really shouldn't work. The audio would get dropped at the DVI connection points because the "pins" for audio isn't there.

Also, since you have the new mini, why don't you just use the HDMI port and a standard HDMI cable?

And yes i know, DVI doesn't carry audio, but someone forgot to tell my tv that, because it works.

the new mini came with a MDP to DVI adapter, and i was replacing an older mini that had a dvi connector, so all i had to do was plug it in. have a stereo hooked up for surround sound via optical, so don't use the speakers on the tv that much.

ftaok
Jan 8, 2011, 01:59 PM
the new mini came with a MDP to DVI adapter, and i was replacing an older mini that had a dvi connector, so all i had to do was plug it in. have a stereo hooked up for surround sound via optical, so don't use the speakers on the tv that much.
Very interesting. Where did you get the DVI - HDMI cable? I have one from monoprice ... I wonder if it'll pass audio when paired with a miniDP - DVI adapter and a newer Mac.

waw74
Jan 8, 2011, 02:45 PM
Where did you get the DVI - HDMI cable?

monoprice.