as you have ready found out it's not ideal. But you are in luck; the dongle should work connecting to line-out as well. The problem there...is that you have to reach back of the stereo to turn on/off the dongle.
My wife's audiologist sold her a Voiis 'Wireless Gateway' that she is supposed to connect to the stereo. It will broadcast the audio output to her hearing aids so she can hear the TV without turning the volume up excessively. It's a neat idea and it may even work, but I have a stupid question before I try to connect it.
The 'user manual' for the Voiis has a lot of pictures but not much explanation. I'm supposed to connect the unit to the stereo's output but it is not at all clear whether the intended connection is to an amplified output like the headphone jack or to a pre-amp level output. The picture looks like a pre-amp connection with RCA plugs but the unit also includes 3.5 mm stereo plugs like the ones for my iPod ear buds.
I've asked their tech support for clarification but then I wondered if any forum members are familiar with the Voiis devices.
I still have to solve another problem. I can't plug the Voiis into the headphone jack of the receiver because that will turn the speakers off. I'm not quite sure how I'm going to get a sound signal to the device once I know what type input it expects.

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