[Solo0815]

I'm back on 0808 and will do more tests. Has anyone the same problem or a clue, what is causing this underun?

Can you compare #0814 with #0815 and confirm if either build has crackling? If they both do, then the issue is introduced somewhere between #0809 and #0814. If neither has the issue, then the crackling is introduced between #0816 and #0903... Knowing which is the first build with the issue will help a lot. 

I'll try to find the build where the issue started and report here. I haven't found a pattern for the crackling sound atm. It occurs from time to time. A restart helps ...