Akio has done the following roles in audio drama.

Aika [CD]	Aida Gouzou
Ayakashi Ninden Kunoichiban Gaiden [CD] {Volume 1-2}	?
Bouken Radio Movie [CD] {2}	Kuwamizu Gorou
Chou Kousoku Gran Doll [radio]	Grand Knight
Cinematic Sound Drama GetBackers [CD] {Legend of Vampire}	?
Clock Tower 2 [CD]	Samuel Barton
Clock Tower 2 [CD]	Scissorman
Fire Emblem [CD]	?
Fortune Quest [CT]	Bokuboku's father
Fushigi no Umi no Nadia -Yattara kou nacchatta Nadia- [CD]	?
Gekkou no Pierce [CD]	king
Gundam Wing [radio]	narrator
Jojo's Bizarre Adventure [CD]	?
Joker [CD]	Barley
Kidou Senkan Nadesico Oshare Club [CD]	Misumaru Kouichirou
King of Fighters '96 Drama CD [CD]	narrator
King of Fighters '98 Drama CD [CD]	narrator
King of Fighters 97 Drama CD [CD]	narration
King of Fighters 97 Gekitotsuhen [radio]	narration
King of Fighters 97 Shukumeihen [radio]	narration
Luna Silver Story Lunatic Festa [CD] {Vol 1}	Dain
Luna Silver Story Lunatic Festa [CD] {Vol 2}	Reiku
Marouou Fuu'unden [?]	?
Metal Gear Solid [CD]	Solid Snake
Psychic Force [CD, radio]	narration
Sampaguita [CD]	?
Scramble Wars "Yami no Labyrinth" Drama Hen [CD]	Zackson
Shadow Skill [CD]	Scar Face
Street Fighter EX [radio]	narration
Street Fighter II [CD]	?
Tohshinden -Before Stage- [CD]	?
Twin Signal Sound Theater [CD]	?
Vampire Hunter [radio/CD]	Demitri
Vampire Hunter Gaiden: Shukumei no tabibito Donovan [CD]	NA