image load sometimes fails when concurrent directory listing is happening

in first shell running:
```dd if=/mnt/neptune/tagbin/0.4.63 of=sd/0/img/0.4.63 status=progress```

in second shell running:
```ls ~/tags/a0b696b4fb29/tag/sd/0/img;    sleep 1```

Sometimes the ```dd```  fails with 'no such file or directory'. Fails at various offsets in the image load.