it looks like your Sony STR-DA1000ES receiver also has a digital coax input. If you aren't already using it, you can use it if one of your devices has a coax output. Since it is digital, it will provide the same sound quality as the optical inputs.
Last question, why does the tv optical digital output cable send only OTA audio and not send all devices DD 5.1 signals to the receiver since all are connected to the tv via the hdmi inputs ?
A lot of TVs have this limitation, which I think is because the chipset that processes the HDMI inputs only handles stereo.