E190 Audio Control Panel bug
 

Normally we use #1 VHF for ATC communication,but keep both VHF #1 & #2 receiving ON,If you want use VHF #2 for transmit,for example you want talk to company,whan you select VHF #2 MIC,Be careful,the VHF #1 receiving may de-selected automatically.This is not normal.

I am no engineer but I think the reason for the VHF1 to deselect when you select VHF2 to trasmit is because when you initially selected VHF1 you only pressed the Microphone selector (Square shaped button). that also caused the Audio selector Button for VHF1 (round one) to illuminate.

Due to the Fact that you were not listening out on VHF1 Before you pressed the Microphone selector button for VHF1 it assumes that by deselecting the microphone selector button or by selecting another Microphone selector button that you no longer want to listen out on VHF1.

Another thing I don't like about this ACP is the fact that while you are in the process of transmitting, You cannot change the volume of what you are listening to. Eg. say you are monitorring VHF2 on high/same volume as VHF1.

while you transmit on VHF1 if you recieve a transmission on VHF2 you are forced to deselect VHF2 because you must wait to stop transmitting before you can lower the volume.

Nothing wrong with the ACP, it's just probably very different to what you've been used to!

If you start pressing buttons just for the sake of it, you won't get what you want. Like everything on this type, you need to do thing's with a purpose and not just by guessing (and pressing). After a while it becomes like any other aircraft.

Today I flew another plane,check the ACP again ,then I found one of three ACP got same defect ,after M/M swap panels,things become very clear,It's ACP quality problem.