I had a unit for a while (can't remember make). It works ok but you need to be very careful when setting the input volume level to the transmitter. I was getting clipping on the receiver. I noticed something going on so I connected a little oscilloscope box I have that plugs into my notebook and sure enough I was getting a clipped signal. I had to really turn down the input gain on the transmitter. I stopped using it soon after that.
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