Hi, I see PR build fails because i changed the header of UAC module api `uacb->req_send = uac_req_send;`. The solution(s) I can see right now are either: 1. Guard the uac_req_send(void/int) by some compilation #define or 2. Get the tm module 'enable_uac_fr' config parameter value inside `uac_req_send(void)` function and decide adding TMCB_ON_FAILURE if it is enabled or not. or 3. Adapt the test function with an parameter of "0"