DA7212 - Mic_1 echoes the same audio played over HP_L/HP_R

Hi there.. thanks for coming to the forums. Exciting news! we’re now in the process of moving to our new forum platform that will offer better functionality and is contained within the main Dialog website. All posts and accounts have been migrated. We’re now accepting traffic on the new forum only - please POST any new threads at https://www.dialog-semiconductor.com/support . We’ll be fixing bugs / optimising the searching and tagging over the coming days.
1 post / 0 new
Last seen: 2 years 1 month ago
Joined: 2018-09-21 07:56
DA7212 - Mic_1 echoes the same audio played over HP_L/HP_R

In our application, we are using DA7212 as audio codec for Bluetooth headset. 1.2k Ohm analog mic is connected to Mic1_P/Mic1_N in differential mode. Following are the mic configurations,
MIc_bias = 0x08;
mic_1_ctrl = 0x80;
mixin_L_select = 0x02;
mixin_L_ctrl = 0x88;

mixout_L_select = 0x08;
mixout_R_select = 0x08;

Our application needs simultaneous working of Mic_1 and HP_L /HP_R with out echo. I'm observing an echo of audio played over HP, please note that the echo is still present even if I haven't connected mic.Is there any other register to look for? As the datasheet says DA7212 has true ground, echo shouldn't have happen and the design of this board is with reference to eval board.