Hi Sean,
The flashing red and green lights on a B2 indicate a problem loading the B2's Operating system form its internal SD Card
As you B2 is a newer type model it holds its music on an internal HDD (or SSD) which is a separate device to the SD Card. It is almost certain that your music is OK.
The easiest thing for your to do is to order a new SD Card (preloaded with the B2 software) from the Brennan web site
here
Note the two models, if you have a B2 where a card sticks out of the right hand side order the top one. However I think your model will require the new Micro SD Card version, in which case to change it you will
need to open the case as described
here
Once you have installed the new SD Card the first thing to do is a "Web Upgrade" to ensure that you have the very latest software release version (the one on the card may be slightly out of date). After that you will
be up and running.
Now, If you want to write an SD Card of your own (Which is possible and easy to do) please tell us and we will guide your though it - however for £10 the Brennan off the shelf option is easiest !!
Fred