Problem with Audio-Technica AT897

I'm having trouble using the Audio-Technica AT897 shotgun mic with the BMCC. When I hook up the mic everything works great for about 5 minutes, then the camera audio input switches to 'Line' and I can't change it. I have to unplug the mic and plug it back in. I tested the mic and cable with an audio interface and it recorded hours of audio without interruption. Anybody else have this kind of problem?

I've only tried audio once on my bmcc, I was using this mic going through a mixer, and into the camera. It would also do the switch to Line after a little bit. Now i've heard the camera will do this if your audio is clipping for about 5 seconds, in order to protect itself. But my mixer wasn't even getting halfway up to the peaking point on the mixer (mid green, with things cranked up) Once I get my computer back I can test audio using Ultra Scope. I dont think its the mic thats causing the issue, as I've used it with one of those H4n Zooms and its been great. I think its just the camera needing some audio tweaks in a firmware update.

I'm having trouble using the Audio-Technica AT897 shotgun mic with the BMCC. When I hook up the mic everything works great for about 5 minutes, then the camera audio input switches to 'Line' and I can't change it. I have to unplug the mic and plug it back in. I tested the mic and cable with an audio interface and it recorded hours of audio without interruption. Anybody else have this kind of problem?

It's a feature of the BMCC that it switches into line level mode automatically from mic level if the audio input severely clips. It's described in the BMCC user manual.

There are other threads here discussing techniques for getting good audio with the BMCC. For example, see:
viewtopic.php?f=2&t=6747&hilit=audio
viewtopic.php?f=2&t=7124

To prevent damage, the camera will automatically switch to line level input if the input levels are over the limit for a sustained period of time.

This is one of the most frustrating "features" I've ever come across in a camera.

What's worse is that if you overload the "line level" input - then the camera basically just shuts down the audio completely (which you won't know unless you're monitoring the headphones), and you have to do a power cycle for it to come back to life.

Personally, I would NEVER connect a microphone directly to this camera. I would ALWAYS use an external mixer.

To prevent damage, the camera will automatically switch to line level input if the input levels are over the limit for a sustained period of time.

This is one of the most frustrating "features" I've ever come across in a camera. ...

I agree.

... What's worse is that if you overload the "line level" input - then the camera basically just shuts down the audio completely (which you won't know unless you're monitoring the headphones), and you have to do a power cycle for it to come back to life.

You'd of course always be monitoring via headphones, right?

... Personally, I would NEVER connect a microphone directly to this camera. I would ALWAYS use an external mixer.

"NEVER" is a long time. I hope BMD will sometime soon update the camera's firmware so its audio performance & behavior is improved. In the meantime, I also plan to use an external mixer with my BMPC-4K when I eventually receive it.

Cheers.

You'd of course always be monitoring via headphones, right?

To be perfectly honest... no.

The headphone jack on the camera is simply too noisy and painful for accurate monitoring over the course of a day. It doesn't give an accurate representation of what's actually being recorded.

What I do currently is monitor the return feed at the start and end of each take - but during the take, I listen to what actually coming into our external mixer.

However, in future, what I'm hoping is that I'll be able to get a decent audio feed from the HDMI port for constant monitoring.