No sound 50+% of the time in calls, until reboot

[BertG]

Glad your problem seems to be solved and quite understandable, that you got some reservations to consider it solved. I would as well.

Though:

@Bas_tien

Anything about SIM card and other issues they have posted on their blog is NOT related to the issue described in that thread

In some cases it might be related and therefore still something worth checking out. See this citation from a posting in another thread of yours:

@Michiel

However, one of the things they asked me to do what to request a new SIM from my provider, and a while ago I did. I got a new one a few weeks ago and put it in. Now, the trouble is, my phone is more a pocket computer than a phone and I don’t get called a lot. But today, I got two calls, as in you know that outdated technology kind of thing, non-VOIP stuff, and they both worked. I wasn’t expecting that at all, and was very surprised I could hear the other end.