Greetings,
 
It may seem a silly question, but I've just started to study Old Norse and this is the main thing annoying me right now:
 
In words with final consonant clusters that end in "-r", such as "maðr", what is the pronunciation? Is a medial "-u-" inserted in speech? Since Modern Icelandic features such insertion in the written language itself, it seems very plausible, as far as morphological changes are concerned, assuming the modern pronunciation reflects the old one.
 
Could someone confirm this?
 
Thank you in advance.
 
Gabriel