GH4 Loses Sound at 24p @100mbps at DVinfo.net

Craig McKenna · August 21st, 2014, 12:40 PM

Hi All,

I'm in love with the GH4, but I had a huge headache at a wedding recently when sound appeared to disappear without warning. I was unable to find the fault until the following wedding, when I'd had sound working again for some time. Switching to 24p @ 100mbps, the sound fault appeared again, with the left and right channel icon disappearing and no sound being recorded.

I'm currently using v1.1 firmware. Completely bamboozled by this issue, as sound records perfectly in every other mode - so thankfully, I can get around it.

My question is: Does anybody have any ideas as to how to fix this? Heard any other users with a similar problem? Know what I should do next to rectify this problem?

Thanks!

Bryce Comer · August 21st, 2014, 02:21 PM

Are you trying to do overcranking in 24p? If so, that will be the problem, as no sound is recorded in that mode.
Regards,
Bryce

Craig McKenna · August 21st, 2014, 02:43 PM

Quote:

Originally Posted by Bryce Comer

Are you trying to do overcranking in 24p? If so, that will be the problem, as no sound is recorded in that mode.
Regards,
Bryce

Hi Bryce,

Can you please explain what overcranking is? I haven't tried to do anything (knowingly) except to record to that format.

Thanks for your input though!

Craig

Bryce Comer · August 21st, 2014, 08:13 PM

HI Craig,
It's the variable frame rate you need to check. Go into the menu where you change the setting to 24p & just under that you will see the variable frame rate options. If this is on, no sound will be recorded. Turning variable frame rate off will get your sound back. Assuming of course that that's the problem. Good luck.

Craig McKenna · August 22nd, 2014, 03:46 AM

Quote:

Originally Posted by Bryce Comer

HI Craig,
It's the variable frame rate you need to check. Go into the menu where you change the setting to 24p & just under that you will see the variable frame rate options. If this is on, no sound will be recorded. Turning variable frame rate off will get your sound back. Assuming of course that that's the problem. Good luck.

Thanks for this! I wish I knew that beforehand! :/

Can you explain why this occurs? I was unaware that this would happen, even after reading lots of information about going to 96fps...!

Such a relief that I don't need to do anything else to 'fix' the camera.

Bryce Comer · August 22nd, 2014, 10:12 AM

Yes it's a bit of a bummer for sure. None of the cameras i've had that have done overcranking have recorded sound. Not sure any that do overcranking will record sound.
Is it the slow motion you are after? If not, & you simply want to record in 24p then you can simply turn off variable frame rate. You could always record in 60p & slow the footage down in post, that way you will keep your audio intact.
Bryce

Craig McKenna · August 22nd, 2014, 06:44 PM

Quote:

Originally Posted by Bryce Comer

Yes it's a bit of a bummer for sure. None of the cameras i've had that have done overcranking have recorded sound. Not sure any that do overcranking will record sound.
Is it the slow motion you are after? If not, & you simply want to record in 24p then you can simply turn off variable frame rate. You could always record in 60p & slow the footage down in post, that way you will keep your audio intact.
Bryce

I didn't realise that it was referred to as 'overcranking' - I just thought it was a strange way for the GH4 to reach its 96fps mode! Now I realise what it means and how it performs the task from the term... cheers!

I was after slow motion for some parts of the wedding, which is why I think I invoked the VFR during the preparation... I was planning to shoot 24p for most of the wedding, but using VFR to easily switch for the aisle walk etc. The way I saw it in my head was, that I could remain in that mode but just switch the VFR at times I preferred. Now I realise that it's best to stick with what I knew before - switch between the modes themselves, even if they can't do up to 96fps - 60p is enough!

I have always used the 60p mode (on the GH3) for slow motion... but I've always been unaware of this issue with overcranking... as I've never tried it before.

I've turned it off now, thanks! It's a massive help to know the cause and also to know that it's of no fault of the camera - just the user! ME! As usual! Haha.

Thanks Bryce... really helpful! Appreciate it!

Craig

August 21st, 2014, 12:40 PM	#1
Craig McKenna Major Player Join Date: Nov 2013 Location: Liverpool Posts: 495	GH4 Loses Sound at 24p @100mbps Hi All, I'm in love with the GH4, but I had a huge headache at a wedding recently when sound appeared to disappear without warning. I was unable to find the fault until the following wedding, when I'd had sound working again for some time. Switching to 24p @ 100mbps, the sound fault appeared again, with the left and right channel icon disappearing and no sound being recorded. I'm currently using v1.1 firmware. Completely bamboozled by this issue, as sound records perfectly in every other mode - so thankfully, I can get around it. My question is: Does anybody have any ideas as to how to fix this? Heard any other users with a similar problem? Know what I should do next to rectify this problem? Thanks!

August 21st, 2014, 02:21 PM	#2
Bryce Comer Trustee Join Date: Jun 2007 Location: Rossland, British Columbia Posts: 1,024	Re: GH4 Loses Sound at 24p @100mbps Are you trying to do overcranking in 24p? If so, that will be the problem, as no sound is recorded in that mode. Regards, Bryce __________________ There's never enough hours in the day!

August 21st, 2014, 08:13 PM	#4
Bryce Comer Trustee Join Date: Jun 2007 Location: Rossland, British Columbia Posts: 1,024	Re: GH4 Loses Sound at 24p @100mbps HI Craig, It's the variable frame rate you need to check. Go into the menu where you change the setting to 24p & just under that you will see the variable frame rate options. If this is on, no sound will be recorded. Turning variable frame rate off will get your sound back. Assuming of course that that's the problem. Good luck. __________________ There's never enough hours in the day!

August 22nd, 2014, 10:12 AM	#6
Bryce Comer Trustee Join Date: Jun 2007 Location: Rossland, British Columbia Posts: 1,024	Re: GH4 Loses Sound at 24p @100mbps Yes it's a bit of a bummer for sure. None of the cameras i've had that have done overcranking have recorded sound. Not sure any that do overcranking will record sound. Is it the slow motion you are after? If not, & you simply want to record in 24p then you can simply turn off variable frame rate. You could always record in 60p & slow the footage down in post, that way you will keep your audio intact. Bryce __________________ There's never enough hours in the day!