Keywords: HT4189, 4189, Amazon prime, Netflix, hulu, no sound, Dolby/DTS
Netflix and Amazon prime audios are tested working well with any of Avantree transmitters or TV set, as far as the settings are correct.
If not, please double check your settings.
If you connect your transmitter to your cable box audio out. And your Amazon prime and Netflix are going through your smart TV streaming system, then you surely will not be able to hear audio from these two channels from your Bluetooth headphoens.
If you do connect your transmitter to your TV, and still experience the same, then you need to ensure:
1) Your TV Audio Format is set to "PCM", NOT AUTO or "DOLBY/DTS". (Bluetooth adapter does not decode Dolby/DTS)
2) Change your TV audio out setting to "External Speaker".
If above suggestions do not help, then your TV does not regulate the audio from these two streaming services to PCM properly and a Digital Analog Converter like this will help：