The name has been somewhat obscured by the Latin scribe who uses Burgundian styling. But the elements seem to be
Aud- wealth (OE Ead-) related to a verb Audan- (Eaden-) grant, give; and redaz ( often with umlaut to rad) thought, advice, from a root meaning think, arrange, (put in) order. It's earliest onomastic uses rad may have had indo-Iranian influences in which what is put in order is not ones thoughts but ones estate.