I just bumped into this and had to share it. Jason Griffith, who most know voiced Sonic in the Sonic X anime in 2003 until Sonic and Sega All-Stars Racing in 2010, actually did indeed still voice Sonic for at least one last time in a half hour Fall 2010 Preview of Toonzai on CW4Kids. You can see the full video below.
Sonic himself confirms this aired on September 3rd, 2010 as pointed out at 4:28 in the video. This is very interesting as it was on July 15th, 2010 when the cast change was announced and Roger Craig Smith was to take over as Sonic officially starting with Sonic Colors and Sonic Free Riders. Roger actually had already voiced as Sonic in the Sonic Spinball ride earlier.
And to top it off, you heard right, Sonic is indeed talking about Dragon Ball Z, in name. That’s pretty mind-blowing to witness isn’t it?
Oh and Sonic sez Piccolo is a Saiyan apparently.
Via zzcolby27 on YouTube.