excel json import

I have a file of json data, which has some headers, and then a list of data values. Each data value is a list of two values [ time, value].

When I do a json import to excel, I just get the top level specification lines, and then it shows "[List]" for the values list, with each entry being a [List] of two un-named values.

I can drill sown, to ssee the list of all data [List]'s, or drill down again to see the two values of one data point list.

I want to convert the whole thing to a csv with all the [time,value] pairs.

  {     "username" : xxxx,

       ....

       "allData" : [

              [   11, 12 ],

              [   12,  22],

          ...

             ]

]