OK I think i worked out what my problem is - see this thread (
https://www.oesf.org/forum/index.php?showtopic=23984&st=75&gopid=178010&#entry178010)
It says in there that the kernel developed for Quasar media player causes issues with USB HDD however someone else also says that these changes have been rolled into Tetsu's kernel (which presumably would work fine with external USB HDD's)
Also I just double checked and it said sharprom/cacko so I guess I'm still running sharprom with this kernel so any references to cacko are my mistake - i am not running cacko - just sharprom with this special kernel.
Sooooo......
I guess the answer is to install Tetsu's kernel - of course as I can't read his website (I don't speak japanese)
so I downloaded what I think is the right kernel (18j C3200) and also kernel-modules_v18j_arm.ipk and updater.sh. However in some of the english translated stuff I could see that 18j was talking about dual booting into PDAXROM which I don't want to do but I can't see the earlier Kernel on his website to download. Oh well I guess it supports it but hopefully doesn't require it?
So I think what I need to do is
- Install the new kernel
- Install the IPK with the modules
Test again - can someone else make sense of this and see if my approach makes sense?
Thanks!