How do you have the video format setup on your TiVo? Seems like your TV is doing the video conversion to 1020p and its causing the sync problem with your receiver. You could try letting the TiVo do the video conversion before it reaches your receiver and let your receiver pass it though to your TV.
Try playing around with the Video formats on your TiVo.
S2, S3 (OTA), TiVo Hd, Premiere (OTA), Roamio Basic (Comcast Cable).