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?