HO-DirAC: wrong index for diffusenes in the rendering

Basic info

• Commit SHA: main
• Platform:

Bug description

HO-DirAC accesses the diffusenes in the subframe rendering routine via the DirAC read index, this index at this point is already incremented to point at the next subframe after the currently processed one

Ways to reproduce

(Clear steps or refer to a failing automated test, e.g. with a pipeline link)

similar as #393 (closed)