Yes, please try it with ASIO. With audio, I can seek back and forth with no issues. Only a pause causes the issue. With movies a seek does cause the issue. Is a seek for movies different than a seek for just music?
Unfortunately I can't use WASAPI because my device only then allows 6 channels. I don't know why it can't use 8. It is the same with DirectShow. ASIO is the only output that allows me to use 8 channels.
I just tried some more stuff and happened to find that a new ASIO driver was released on 10/17/12. It isn't on the Steinberg website, but it is on the Yamaha website. I installed it and it made no difference.
The strange thing is this all worked before I decided to add new SSD drives and reload my O/S. However, now I can't get to work even on two different computers.
One interesting thing I found through all this is that my device allows me to specify the output routing. The default with JRiver is to use channels 0-7. This corresponds to Mix 1/2, Mix 3/4, Mix 5/6, and Mix 7/8 on the outputs. If I used a mic and tried to record with REW I would get feedback. I never could get it figured out. I realized I can put the offset in JRiver to 8 and now it will output to DAW 1/2, etc. This bypasses the mixer completely. I was trying other software to test my ASIO and one of them allowed me to select DAW 1/2 as my first two channels. I tried it, but got silence. I then changed the output routing in my audio drivers and got it to work.
I say all this to suggest that maybe JRiver show the ASIO outputs available rather than just asking for an offset.