Sony CFExpress Type A <100MB/S Transfer Speed to M1 Max MBP

[michaelalpinephoto]

I have a 160GB Sony CFExpress Type A TOUGH card that I use with a Delkin Devices CFexpress Type A & UHS-II SDXC Memory Card Reader connected to my M1 Max Macbook Pro (running the latest Ventura OS) to move RAW files from my A7IV. I purchased the setup approx. 4 months ago. If I recall correctly, I got around 500-600 mb/s when moving the files from the camera to my computer and sometimes directly onto my Sandisk Professional G-Drive 4TB SSD. 

After a 2-month hiatus from photography work, I am now getting less than 100 mb/s speeds, doing the same workflow, and seemingly without any changes. During that same period, my Sandisk SSD became virtually inoperable (only 4 months old) and is now being replaced by Sandisk.

I don't know if it's an issue with the card, card reader, or computer, or me.

Can anyone help?

Edit 1 - I ran a BMD disk speed test and selected the card connected with the reader as the target drive.... ~35mb/s read/write. I know this cannot be normal.

Edited August 27 by michaelalpinephoto
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[FunWithCameras]

Wow! That's slow.

I'm using Sony's CFeA / SD reader and transferring from the reader to an external SSD (in my case a Samsung) or to the internal SSD on a Mac Studio (also M1 Max), also using Ventura. The reader is connected to one of the front ports, so it's USB-C, not Thunderbolt.

I am getting much faster results than you are.

Thoughts on what it might be:

1. cable? A damaged cable might force the transfer to drop down to something slow (unlikely, but I'd try another cable)
2. card? I don't know if CFeA has a downgraded connection mode (like when a UHS-II SD card has a damaged pad and drops down to the much slower mode that only uses the front row of pads - that mode tops out at 95MB/s).
3. reader? maybe one of the contacts in the reader is bent and not touching the card? Maybe try a transfer from the camera? That should let you eliminate the card and cable as culprits?

Let us know if you find the source of the problem, please.

[Pieter]

4. Port? If connected to a USB-C 2.0 port, transfer is capped at 60 MB/sec. USB-C 3.0 can transfer at up to 625 MB/sec so any gen 3+ port should be fine.