Factory Amp location in 09 Yaris Hatchback

[Harpsped]

As the title suggests, this is about the amp location. According to the connections I have going into the stock head unit, I have an amp connected. However try as I might, I cannot find it. Its not under the seats and it isn't in the rear of the vehicle. I may be blind, but I don't see it where it would be like in the Tacoma; under the head unit. So, I am lost.

The reason that I am trying to locate it is because I recently lost audio from the factory unit although it does still have power. I'm attempting to troubleshoot prior to making aftermarket purchases.

Thanks in advance!