It comes down to what you think Sola Scriptura means. One problem lies in terminology. Sola Scriptura does not mean that Tradition is bad or irrelevant. If it was, then almost all of the content of Confessio Augustana is irrelevant. In the Lutheran tradition, Sola Scripturameans that Scripture is the highest authority. That doesn’t mean, of course, that it is easy to understand, or that no one can, or must, be charged with its interpretation. Again, Sola Scripturadoesn’t mean, in the Lutheran tradition, that we do not need an interpretive office. It simply means that this office doesn’t stand above Scripture, but is its servant, as a supreme court judge doesn’t stand above the constitution but serves and upholds it.
In many ways, Scripture is the equivalent of a constitution. A constitution has primacy, but you can have other, binding, laws, as long as those do not contradict the constitution. To use modern terminology, the Lutheran position known historically as Sola Scripturawould better be described as Prima Scriptura.
And this is, incidentally, also the position of Dei Verbum, and of Joseph Ratzinger/pope (em.) Benedict XVI. In Dei Verbum, this is pointed out in paragraph 10:
This teaching office is not above the word of God, but serves it, teaching only what has been handed on, listening to it devoutly, guarding it scrupulously and explaining it faithfully in accord with a divine commission and with the help of the Holy Spirit, it draws from this one deposit of faith everything which it presents for belief as divinely revealed.
In Dogma and Preaching, which is available on Google Books, Ratzinger presents his case, on pp.26-39. What Ratzinger says there is that Scripture, Tradition, the Magisterium, and the concrete, contextual faith of the faithful depend on each other, but that primacy belongs first to Scripture, then to Tradition (focusing on the Creeds and Dogmas), then to the Magisterium (the servant of Scripture and Tradition), and then to the concrete faith as it is lived out in the dioceses and parishes. One key passage comes on page 38: “[T]he Bible has such an absolutely unique normative importance because it alone is really the sole book of the Church as Church.”
We find the same pattern in Lutheranism: Scripture is the norm which norms other norms (norma normans non normata); Tradition (with emphasis on Creeds and Dogmas, and on liturgy and Canon Law) are norms that are normed by Scripture (norma normata); the ordained priesthood, with the bishops as leaders, has the task to preach and interpret that which has been handed over (Confessio Augustana 4, 28); and this has to be lived out in the context of the faithful’s own lives.