Hello - we continue to have problems sending faxes through ATA 190's. We have success with receive but send continues to be an issue. We use T.38 and eventually will be going to an ITSP for centralized trunking but currently use PRI. This is the flow ATA190 > SIP>CUCM>SIP>PSTN GW>PRI. Below are the steps we have taken.
ATA 190: 1.2.2 (003)
Set T.38 in CUCM
Disable ECM in CUCM
global config: fax protocol t38 version 0 ls-redundancy 0 hs-redundancy 0 fallback pass-through g711ulaw h323