DELL Switching Help - Consistent Packet Loss on User VLAN

Hi All,

New to the community.  After an acquisition of a small office, I’ve recently inherited a DELL network environment. I’ve always worked in Cisco shops, but the past few years I've focused entirely on voice/video. Our sr. network engineer just quit, so i'm back in the hot seat.  The previous sysadmin of this new site left during the transition, so I’m doing the dance of discovery/support.

After migrating the site from onprem VOIP to a cloud PBX(last week), we started getting complaints of call quality.  A few pingplotter scans to the cloud pbx showed all our packet loss occurring on the LAN side.  after some more testing I isolated the packet loss to the user VLAN . ( pingplotter on a local server hit the internet with no packets dropped).  The VLAN gateway on the core switch (s5000) seems to consistently drop packets (3-5%), which is killing voice quality.

After a quick call to DELL I found the switches are out of warranty, so a call with support would be BIG $$$.  I decided to kick the cores after business hours to try and shake things out (this was an hour ago). It's worked before! Unfortunately, packet loss started popping up again 10 minutes after the switch reload.

Feeling a bit defeated, but I have tomorrow morning to troubleshoot further, as I’m ET based and this office is on the west coast.  I’ll be calling DELL tomorrow, but wanted to see what the community thought.  I’ll be posting some config files once I hit the office; sorry I know it’s a party foul to ask questions without giving you guys hard data.    

The mile high environment...

MDF

• S5000- core
• 3048
• 3148

IDF

• 3048 - fiber run to S5000
• 3148

while the network has a small footprint, the only oddity is that internet comes into the IDF and hits a sonicwall FW then the L3 3048 switch.  This traffic is then routed to the MDF S5000 switches.

I finished the night by starting fresh pingplotter scans.  One PC serviced by the MDF access switches, the other PC by the IDF.  My thought being,  if one comes back clean and one doesn’t, I’ll know to focus on either the IDF 3048 or the MDF S5000 ( from a routing perspective)

Any advice would be huge, sorry for the wall of text!!