Doesn't the AD upsampler output the wrong data justification for the SM5842? If so I don't think you can use the SM5842 without conversion in between. You have to use a couple 74ALS163 to convert to the correct justified data that the 5842 accepts. I think most of the work has been done for you if you check out the JtDAC3.
Also the AD upsampler has a software control mode you may want to check out which may give you the format option you need.
You could test the theory by bypassing the sm5842 on your board and run straight from the upsampler to the AD1865's (it unfortunately will be mono) but it would indicate the issue.
Also the AD upsampler has a software control mode you may want to check out which may give you the format option you need.
You could test the theory by bypassing the sm5842 on your board and run straight from the upsampler to the AD1865's (it unfortunately will be mono) but it would indicate the issue.