Creator Backlash: Ben Hurst expressed a contempt for writing for the series, disliking the premise and having a bad time working with the material of other staff. To add insult to injury, this was pitched in favor of continuing his previous beloved project, Sonic SatAM.
Cross-Dressing Voices: Jaleel White as Sonia. Oddly though, if one watches an episode of Sonic Underground, you can tell the voice Jaleel White uses when providing the voice of Sonia sounds inconspicuously identical to the high-pitched voice White used from his other (more) famous role as Steve Urkel.
Non-Singing Voice: All three hedgehogs had three separate voice actors for the singing segments - Samuel Vincent for Sonic, Tyley Ross for Manic, and Louise Vallance for Sonia.
More episodes of this show were planned, but never went beyond the planning stages. Ian Flynn, head writer of Archie Comics' Sonic the Hedgehog, stated that he wanted to write a conclusion in comic form (helped by the fact that the cartoon was established to be in the comic series' Multiverse in an earlier story), but Executive Meddling ultimately prevented this.
Early concept art shows Queen Aleena (a.k.a Sonic's Mom) with a different design.
According to Ben Hurst, this series would have at one point been a continuation of Sonic SatAM. Instead, it was decided to retool the concept completely and make it into a separate series, much to his chagrin.