2014 toyota avensis 2.0d4d headunit upgrade

[2009joe]

hi everyone quick question i have noticed that with my car that i bought the 2014 toyota avensis 2.0d4d business edition the touch 2 headunit tbh sound quality and volume is nothing great considering it has 6 Speakers. my old seat car had 4 Speakers and the sound on that was great .i notice the volume on the avensis headunit at max is not overly that loud .have any of you guys got any ideas of maybe putting in a better amp and speakers  in it and maybe a base speaker .

[2009joe]

so i take it there are no ways of upgrading this toyota touch 2 headunit i have.the sound dont go up as loud as i like and the base sound is not as good . my last sound system on my seat car was better it was a aura premium sound system .im not sure if can connect a amp to this headunit and maybe a sub any ideas out there guys