You can utilize the mp3ReadID3Tags property to tell Wowza not to look at any of the ID3 tags. Sometimes it may be the case that the tags are sub-standard and cause problems for a stream deeming it invalid.
Under MediaReader/Properties in conf/[application]/Application.xml.
<Property>
<Name>mp3ReadID3Tags</Name>
<Value>false</Value>
<Type>Boolean</Type>
</Property>