Male dwarfs and especially Robos can be smelly, not all though.
Ozzy's cage always smelled of old, smelly socks and this had nothing to do with pee spots or cleaning.
Pancake was another one.
Scottie is the same even though i know where his two pee spots are so can spot clean them. I used to clean his HH by removing everything, never found any damp, pee smelly substrate and replaced most of the substrate with fresh once but two days later his HH was smelly again.
I then accepted that i had another little stinker.
Bernard is taking this to another level but could have something to do with living in a tank and tanks don't have good ventilation like barred cages.
I will take the roof off his house and check under the platform to rule out any damp pee patches or gone off fresh food. If i can't find anything like that then i will simply accept that i have another little stinker and leave him to it.
It is not a smell i find offensive, it's more of a natural smell like being in a farm yard.