this is all set up but unless my main box is permanently on nothing records on the mini - Virgin never informed me this would be the case as obviously it’s costly to have the box permanently on just so that the mini can record.
That's 360 operating as designed. On the TiVo-platform, all V6 & TiVo boxes have hard-drives of their own and can independently record and multi-room stream. Ideally you'd have upgraded the TiVo for a V6, and then separately converted both V6 into 360 - and retained the storage.
As it happens, your TiVo has been swapped for a 360-mini which has no HDD of its own, but relies on the 360-master for all recording capability. You can set & view recordings on the mini, but it's slaving from the master.
Unfortunately for yourself, this is how 360 is designed. You should set the 360-master to either fast-start or active-start to enable mini-box recording & streaming.
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