LTM TCP statistics - Received Reset

I have a problem finding information about BIGIP-LTM statistics.

We have a very important application, whith long-lasting sessions. When viewing the VS statistics with the TCP profile we see the following:

ltm virtual /Infrabel/a1183-tms-imi_vs {
    destination /Infrabel/10.252.13.204%113:6039
    ip-protocol tcp
    mask 255.255.255.255
    partition Infrabel
    persist {
        /Infrabel/a1183-tms-imi_sticky-mirror {
            default yes
        }
    }
    pool /Infrabel/a1183-tms-imi_pool
    profiles {
        tcp { }
    }
    source 0.0.0.0%113/0
    source-address-translation {
        type automap
    }
    vs-index 160
}

------------------------------------------------------------------
Ltm::Virtual Server: /Infrabel/a1183-tms-imi_vs
------------------------------------------------------------------
Status                         
  Availability     : available 
  State            : enabled   
  Reason           : The virtual server is available
  CMP              : enabled   
  CMP Mode         : all-cpus  
  Destination      : 10.252.13.204%113:6039
  PVA Acceleration : none      

Traffic                             ClientSide  Ephemeral  General
  Bits In                               271.7M          0        -
  Bits Out                              267.2M          0        -
  Packets In                            658.9K          0        -
  Packets Out                           734.9K          0        -
  Current Connections                       43          0        -
  Maximum Connections                       44          0        -
  Total Connections                       2.9K          0        -
  Evicted Connections                        0          0        -
  Slow Connections Killed                    0          0        -
  Min Conn Duration/msec                     -          -    59.9K
  Max Conn Duration/msec                     -          -   155.9M
  Mean Conn Duration/msec                    -          -    97.7K
  Total Requests                             -          -        0

SYN Cookies                    
  Status                         not-activated
  Hardware SYN Cookie Instances              0
  Software SYN Cookie Instances              0
  Current SYN Cache                          0
  SYN Cache Overflow                         0
  Total Software                             0
  Total Software Accepted                    0
  Total Software Rejected                    0
  Total Hardware                             0
  Total Hardware Accepted                    0

CPU Usage Ratio (%)            
  Last 5 Seconds                             0
  Last 1 Minute                              0
  Last 5 Minutes                             0

  --------------------------------------------------------------
  | Ltm::TCP Profile: tcp           
  --------------------------------------------------------------
  | Virtual Server Name               /Infrabel/a1183-tms-imi_vs

|

| Connections

| Open 86 | Current in CLOSE-WAIT/LAST-ACK 0 | Current in FIN-WAIT/CLOSING 0 | Current in TIME-WAIT 0 | Accepted 2.9K | Not Accepted 0 | Established 2.9K | Failed 0 | Expired 0 | Abandoned 2 |

| Miscellaneous

| Received Reset 2.9K | Bad Checksum Datagrams 0 | Malformed Segments 0 | Out-of-Order Segments 0 | Received SYN Cookies 0 | Received Bad SYN Cookies 0 | SYN-Cache Overflow 0 | Retransmitted Segments 76

Here I see Accepted - Established 2.9K. But I also see Received Reset 2.9K.

When I take a look at the pool statistics, everything seems OK.

Can someone give me more specific explication about this error - where I can find documentation and if possible how we can investigate more (LOG is not an option due to heavy traffic).

Thanks