Has anyone had this problem? I have two HXR-NX5 and both record a buzzing sound every time they write to the SD card and the flash memory unit HXR-FMU128 (about every 10 seconds) this only happens when using external microphones. The problem does not exist using the internal microphone or the shotgun mic that the unit is equipped with. Do I need a special microphone? Is it a grounding issue?

Any help would be appreciated.

Thanks in advanced.

David

It's not the camera. It could be grounding, cables or mics your using, etc. I have a Rode NTG2 shotgun. With one XLR cable there's a hum or buzz. Use another and it's gone. If you're using a wireless, there are many factors that could cause this effect, the most common being around high voltage power lines or a room such as one containing PC servers where there's a high concentration of AC current. Without seeing the exact mics and how they're connected, I can't offer a definite solution.

Thanks for responding but the problem is not AC hum, it is definitely occurring as the camera is writing to the SD card and flash drive. I can see the lights come on when it is writing and that is the only time it makes the buzzing sound.

How are you listening to this buzz. On playback or in your headphones while recording? Have you tried another XLR cable?

Ron Evans

I can hear it loudly in the headphones and of course on playback. It is actually recording the buzz to the audio track.

Yes, I have tried several cables and four different types of microphones.

Update: I contact Sony Service and they were of no help at all. But I did discover something on my own. I tried hooking up a Shure wireless microphone receiver and mic to the camera and the noise did not occur. It seems to me I need some sort of suppressor of filter for all of my other microphones. Does this sound reasonable to anyone else?

I did not get much response on this issue but anyone in the future who may have to deal with this problem here is the solution. I went to a music store where we tried several mics and filters. High dollar microphones did eliminate the buzzing. But There is another solution. It was an isolation filter. Below is the description:

The ISOBLOX by RapcoHorizon offers 600 ohm, 1 to 1 inline isolation. This BLOX allows both signal and ground isolation while retaining a 600 ohm load and source impedance. The in/outs on this isolation box are XLR female and XLR male, respectively.

Hope this helps.

Good information. Glad you found a solution to your [problem.

Just interesting to find an isolation solution works as normally on battery power there is no other ground loop. Did the problem occur on different tripods and power sources?

Ron Evans

I, and others,have had this same problem on the Sony FS-100, a beep every time the card is written to, and is definitely linked to the presence of the FMU. I have two FS-100's, they both exhibit a beeping on Channel 2 (very loud when the FMU is installed, hardly noticeable but slightly present, when the FMU is not installed, basically no problem when the FMU is not installed, and no problem when you don't use Channel 2 in any case). I have used different FMU's with the same result.

Happens regardless of brand of SD card, and regardless of microphone used. (this cam has no internal mic)

The Sony service center says they never heard of the problem. I haven't sent the camera in yet to be checked. They just said send it in. .

Here is the sound:

Beeping on Sony FS-100 with FMU on Vimeo

Ron,

Yes, the problem worked on and off different tripods and with battery as well as the AC adapter.

One thing I did not mention. We also tested another "thing" that worked for the lapel mics I had but not on the handheld. I cannot remember what the "thing" was called but it was under $10. It looks like a metal XLR plug, male on one side and female on the other end. If memory serves me right, the guy said that it crosses (or switches) two of the connections (such as the ground and one of the other leads). Apparently not all microphones are wired the same. This "thing" is a very common item for music stores to carry.

A second "thing" we tried looked and cost about the same (under $10) but it did something very different. If a common signal was present across all three lines then it canceled the signal out altogether. This also worked on the lapel mics but not the handheld. So I purchased the more expensive ISOBLOX because it worked on everything.

Sorry that I can't remember what the "Things" were called.

Unfortunately it is common problem to have cables that are not wired correctly. So with three wires there are a number of choices to get them wrong !!! There are cable testers that show if the cable is correct and as you have found out a lot of adapters that either correct or mask the problem. Still think there may be something wrong with your NX5 though as I have not experienced this problem at all and use the FMU and both inputs all the time. Did you have the music shop test you cables?

Ron Evans

I was thinking an XLR mic is an XLR mic, but finally realized today there are at least three kinds, one requiring external power from the cam, one having an internal battery for power, and a third that needs no power (dynamic mic).

My observation on the FS100 today is that XLR mics that get their power from the camera or do not need power at all don't cause the beeping.

Only the mics that have an internal battery, and are used with the camera switch set to 48v OFF are causing the beeping.

I also note there are two different types of beeps, one tone made by writes to the FMU and a higher pitch, quieter tone made by writes made to the SD card. Sometimes the writes coincide so you hear only 1 type of tone.

That explains why I haven't had the problem as all my mics need the 48volt feed from the camera.

Ron Evans

Ron - You said that you think that there is still a problem with my NX5 however as I mentioned I have two NX5 cameras purchased about three months apart and with a very large number between model numbers. The odds of having the same problem with both cameras is very remote unless it is a standard defect among a large number of units.

Ron, I do really appreciate your input.

That's the way I feel, my two FS-100's with the same issue, were purchased months apart. Before I send the camera in to Sony service (which is pretty hard to find the time), I would like them to say "Yeh, we know what's wrong, and we are going to fix it." So far they haven't said that. They have been responsive and courteous, but haven't offered to pay for the return shipping (both cameras have multi-year warranties with them)

I will not have time to try other mics with my NX5U as I am off for a weeks holiday tomorrow but will try with an old mic I have that has the choice of battery or 48v phantom power when I get back. There may be a problem in the input circuitry as several of you have this problem.

Ron Evans

The ISOBLOX solved my problem on the FS-100, can now use battery powered mics without beeping .

Galen,

After all of the help I have received here on the forum I am glad I could finally help someone else.

I am back from my holiday and have tested my NX5U with my AKG C1000S that can be battery powered as well as 48Volts. I have no noise in either mode when selections are set to 48Volt on the NX5U for phantom power and to just mic when on battery power. This for FMU128 and SD card , just FMU128 or just SD card. SD card is a Patriot LX 32G Class 10 card. All were done with Sony mic on phantom 48Volts Channel 1 with the C1000s being switched between battery and 48Volt supply on Channel 2.

Ron Evans