The newer character models, although are higher polly than the originals and have actual hands, look like plastic due to the bad lighting and clash with the other characters (most visibly, the echidnas in the past).Inconsistent framerate the game will constantly dip below 60 FPS and even 30 FPS at times (this isn't the case on the Wii or emulators, though) in addition, several objects didn't have their logic adjusted for the higher frame rate, and have incorrect behaviour.All the environments in the game (except for Emerald Coast, Lost World and Mystic Ruins to some extent) are overall more bland and uninteresting to look at.Several textures now have compression artefacts that ruin the details (this was also the case in Sonic Adventure 2: Battle, but to a lesser extent).Transparency is also a major issue, with the workarounds making textures look blocky and low resolution.

One of the most note worthy changes is the lighting, which looks more dull than the original and loses some effects such as Sky Base getting darker when beneath the clouds.

Despite coming out in 2003, the graphics manage to look worse than the original game which, by the way, came out in Japan in 1998.

Most infamously, the walkway to the loop in Emerald Coast has broken collision detection. Due to being rushed, Sonic Adventure DX is a lot more glitchier than the original Dreamcast version it came from.

Sonic adventure dx 99 edition