On the Mk2/Mk2a players, the software is configured to call real "hdb" "hdc" instead, for backward compatibility with the original Mk1 player. This can be a bit confusing at times, that's why the kernel calls it hdb, yet in software after booting it is shown as hdc in /dev/

You are getting write errors. That won't get "fixed" until the sector is overwritten with fresh data. Now, one might expect that to just happen naturally -- after all, you are trying to write to it -- but often the error is for an adjacent sector, with strange side-effects, or the drive itself has simply run out of spare sectors for remapping bad ones.

The smartctl tool can give further information on this. Reformatting the drive (low-level format, with "hdparm --security-erase") will likely fix everything. But the cause of such errors is usually dust amongst the platters, and so errors will usually recur even after low-level formatting.

Could be time for a new drive. Solid state is the way to go. There'll be a demo/discussion of the options for that at the Meet on Saturday. The most reliable answer is "Get a CF-Card and an adapter."

Cheers