question

The following statements have been made about flexible budgets.
Flexible budgets enable proper comparisons to be made between actual and expected revenues and costs.
In every variance reporting system with flexible budgets that compares budgeted and actual profit there must be a sales volume variance
Which of the above statements is/are true?
I think the second statement is incorrect because flexible budgets are based on actual quantity and actual figures are also based on actual quantity so the difference in volume or quantity is zero.