TiVo just released a new software update for DirectTV TiVos (3.1.0c).

When it installs it overwrites the old TiVo software. By doing so the cachecard drivers previously installed are no longer there and so caching is disabled.

It is easilly fixed - simply re-install the cachecard drivers and everything will work again.

I would recommend downloading the latest drivers from this site rather than using older drivers as there have been a few minor bug fixes.

BTW - You do not need to run tivoflash again.