A few audio observations and questions about my TNA CE:
When sitting in attract mode, there is a loud hiss from my backbox speakers. Is this common? I found only one old post in this thread that mentioned speaker hiss. When I turn off the power switch on the Lepai amp, the hiss obviously disappears. I haven't dug further to determine if the Lepai is creating the hiss, or if it's coming from the audio source.
I've been through the audio adjustment process from an old post in this thread, reduced the "pre-amp" volume of the LCD display, and adjusted the settings of the Lepai amp. To my ears, I now have it sounding better than before.
One thing that I don't care for is that, with the volume adjusted to have the music at a comfortable level, the FX sounds during game play are annoyingly loud. When I go into the service menu, the sounds that it makes when changing between selections are painfully loud. I could wish for a software setting to set the FX audio levels (sound effects and voice callouts) relative to the music levels.
I'd eventually like to replace the Lepai amp with a class AB car amp and power supply. I'd also like to try taking the monitor out of the audio chain by extracting the audio from the HDMI signal (prior to the monitor) and sending it to a standalone DAC and then the amp. [I'm guessing that it wouldn't work to just plug a USB DAC directly into the small single-board computer.]