diff --git a/audio/aidl/default/Telephony.cpp b/audio/aidl/default/Telephony.cpp
index 1854b35..d873178 100644
--- a/audio/aidl/default/Telephony.cpp
+++ b/audio/aidl/default/Telephony.cpp
@@ -20,8 +20,17 @@
 
 #include "core-impl/Telephony.h"
 
+using aidl::android::media::audio::common::Boolean;
+using aidl::android::media::audio::common::Float;
+
 namespace aidl::android::hardware::audio::core {
 
+Telephony::Telephony() {
+    mTelecomConfig.voiceVolume = Float{TelecomConfig::VOICE_VOLUME_MAX};
+    mTelecomConfig.ttyMode = TelecomConfig::TtyMode::OFF;
+    mTelecomConfig.isHacEnabled = Boolean{false};
+}
+
 ndk::ScopedAStatus Telephony::getSupportedAudioModes(std::vector<AudioMode>* _aidl_return) {
     *_aidl_return = mSupportedAudioModes;
     LOG(DEBUG) << __func__ << ": returning " << ::android::internal::ToString(*_aidl_return);
@@ -38,4 +47,28 @@
     return ndk::ScopedAStatus::fromExceptionCode(EX_UNSUPPORTED_OPERATION);
 }
 
+ndk::ScopedAStatus Telephony::setTelecomConfig(const TelecomConfig& in_config,
+                                               TelecomConfig* _aidl_return) {
+    if (in_config.voiceVolume.has_value() &&
+        (in_config.voiceVolume.value().value < TelecomConfig::VOICE_VOLUME_MIN ||
+         in_config.voiceVolume.value().value > TelecomConfig::VOICE_VOLUME_MAX)) {
+        LOG(ERROR) << __func__
+                   << ": voice volume value is invalid: " << in_config.voiceVolume.value().value;
+        return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_ARGUMENT);
+    }
+    if (in_config.voiceVolume.has_value()) {
+        mTelecomConfig.voiceVolume = in_config.voiceVolume;
+    }
+    if (in_config.ttyMode != TelecomConfig::TtyMode::UNSPECIFIED) {
+        mTelecomConfig.ttyMode = in_config.ttyMode;
+    }
+    if (in_config.isHacEnabled.has_value()) {
+        mTelecomConfig.isHacEnabled = in_config.isHacEnabled;
+    }
+    *_aidl_return = mTelecomConfig;
+    LOG(DEBUG) << __func__ << ": received " << in_config.toString() << ", returning "
+               << _aidl_return->toString();
+    return ndk::ScopedAStatus::ok();
+}
+
 }  // namespace aidl::android::hardware::audio::core