I had these issues in the past couple of weeks as well. Called at least 10 times. One question was tricky, and suddenly the agent "did not hear me anymore". the other 6-7 times I got connected, and it was just silent, then I heard phone beeps again, silent... hung up.
The most weird experience: I got connected. The aAgent could not hear me, but I could hear him. I sort of think I was joined to another call, as the Agent was talking about his favorite music and his old records and hobbies, I heard music in between as well when he played his favorite songs, and he was having a fun time with another person at the other end.
I listened for about 5 minutes, thought it was somewhat amusing (albeit annoying)... but no wonder waiting times are that long if they call privately....