I have a 1993 Pioneer VSX-D9026 receiver (1999) and a Sony Vega SON KV36HS510 TV (2003) the TV only has rca connections. The TV is controlled by a cable box. The audio for the TV comes from the receiver. I connected the Roku and by switching the source on I get video but no audio. There are no HDMI connections on the receiver or on the TV. Can anyone help me fix this?