decrease the keyframe interval, it will make your file bigger, but it will increase the chances it takes for the compressor to get a better reference frame.
NOT an expert on this, but I believe it will work since I had my share of headaches before, one really funny though I think I’ll share. I had to export a low res wmv from a 2min video so the client could approve.
And the AE wmv compressor simple choose to skip the last 15 frames, half a second of logo and some legal stuff. It just held the previously frame for 15 more frames. It took me two hours to figure it out. Lowering the keyframe from 5 to 4 did the job and kept the size restriction they had.