One thing I would check is that your switches (and router, if applicable depending on VPN/connection type) are honoring the QoS the phones are tagging. It is normal for the phones to tag their own packets with VLAN Priority 6/DSCP 46, but many switches won't honor those tags unless they are told to, seems to me Cisco's need commands like "msl qos trust dscp" and "msl qos trust cos", other switches require similar settings or else they will ignore all QoS in the network. However, with those few phones onsite I don't imagine it would make a huge difference in an average office environment... My best guess is that these are phantom alarms, I would just turn them off with the system flag.