A network engineer receives a report about poor quality on an active call between the IP phone of user A over the WAN to the IP phone of user B.
Using web access to the phone, the network engineer remotely checks call statistics such as jitter, network delay, and packet loss. Calculated packet loss is 3%, average jitter is 20 ms, network delay is 1 ms, and conceal seconds is 7.
What is the most likely problem with this call?