I have two AX100s. For about two years I have been using a Lexar Professional 128GB SDXC Class 10 card in each camera. Two cams using same exact type of card. Everything has been working perfectly for about two years.

Beginning two events ago, both cameras have begun freezing up with a buffer overrun message. I have to take battery out to shut camera off. Upon reinserting the card and turning cam back on, I get an option to try and recover data, which I do, and then at some random time later the whole thing happens again.

I switched to two smaller Sandisk cards and the issue does not occur.

I always format cards in camera before each event. After this happened I formatted using PC then formatted again in-camera. I'm shooting in 4K at 60mbps.

At my event Saturday night for a single cam shoot, I used old card and it happened again.

It is very, very weird to me that this happened on both cameras during the same event. I use the cams in tandem for weddings, so they have been used for very similar amount of hours.

Are my cards worn out?

My money is tight and I'm trying to avoid buying new card though I'm thinking I must.

I'm thinking of shooting in 1080i to see if the slower bit rate will avoid this issue, but obviously I'm nervous about it.

Your thoughts?

If your sandiscs don't give the error it can be your 2 lexar cards, how unlikely it may seem, are starting to fail, since you have been able to repeat the error I would not trust the cards anymore. 2 of those Lexar cards are only 160 euro where I live, is your budget that tight it is worth taking the risk of loosing data?

Hi Noa, here the cards are $100 each, and yes my budget is that tight at the moment. I'm reading the issue could be related to bad sectors caused by power failure, and both cameras have run out of battery power while recording on occasion. So I'm trying to find a way to do a low level format of the cards. Some DSLR cams offer that option, but I would need to do it on my PC, so I'm looking for a tool to do that with.

Hi Jeff

This works well on my SD cards

HDDGURU: HDD LLF Low Level Format Tool (http://hddguru.com/software/HDD-LLF-Low-Level-Format-Tool/)

Chris

This company makes a really nice diagnostic tool.

It's called: "Flash Drive Tester v1.14"

https://www.vconsole.com/download

It's free and I have been using it for years. It will test each memory sector/block on your card, map and display any bad sectors. It shows you a really sweet grid and diagram. If the memory block is green, it's good, if yellow, it's questionable and if it's red its a fatal or dead block. It will also give you a raw data speed rating on you card too.

You are going to love this tool. (make sure you use the write and verify option)

CT

Thanks, Chris and Cliff! Great stuff! This evening will try after I've downloaded footage.

I've also found something interesting here: https://www.sdcard.org/downloads/formatter_4/

Cliff, your diagnostic tool showed no errors on the first card. I'm going to low-level format both cards then test them tomorrow in-camera.

I read somewhere that an SD card should last thousands of write cycles, so I'm wondering what's happening.

After reformatting both cards using the SDCard.org tool, I have tested both cameras and have not experienced a recurrence of the original issue.

I'm going to repeat running the cameras and filling the cards again to make sure the issue is resolved.

Thanks Cliff, Chris, and Noa for your assistance!