If the memtest86 shows any errors then you will have to check your RAM sticks, first make sure that they have been installed correctly and then test each RAM separately until you find the faulty one.
What can I do? It only takes one bad experience for the customer to swear off your business forever.
In addition to this, I tried the iOS Teams client to see if it would have its Bit Rate limited by the Media Bit Rate policy setting.
Remember that empathy, too, begins with active listening.