Host (A) record (DNS) updated with wrong IP address

I recently installed a new Domain Controller running Windows Server 2012 (called "srv3") in a domain with two existents DCs that are running Windows Server 2003 (called "srv1" and "srv2"). All roles (DHCP, AD and DNS) have been migrated to the new server and are operational.

The issue is that the A record for "svr1"

I have some network connection problems though, and found out that the host (A) record of "srv1" in the forward lookup zone takes the ip address of "srv3".

I should have :

srv3      Host (A)    xx.xxx.6.4
srv1      Host (A)   xx.xxx.6.1

But I have :

srv3      Host (A)    xx.xxx.6.4
srv1       Host (A)    xx.xxx.6.4

Today I demoted both "srv1" and "srv2", turned them off and deleted the A record for "srv1" but it is still being registered back in DNS and it points to srv3's IP address (which is odd). The owner of svr1's A record appears to be "svr3"

Why would "svr3" create a record for "svr1" (and tie it to svr3's IP address)?

ADDITIONAL INFORMATION

• The output for

  netdom computername srv3 /ENUMerate
  

  is

  All the names of the computer are :
  srv3.myDomain.local
  srv1.myDomain.local
  

• I don't find any reference for srv1 in the content of the netlogon.dns file.

• Procedures followed : After installing and setting Windows Server 2012 on a new server, I installed AD, DNS and DHCP roles using "Add roles and Features". Then I transferred FSMO roles. After setting the new DNS, I found out that client's IP configuration (using ipconfig /all was good (implying new DNS), but the output of nslookup was Default Server: UnKnown. I discovored that the client's group policy was setting "srv1" as DNS. After getting rid of this parameter, some of the clients were connecting well and other not.

EDIT 26/09/2014 15:56 (UTC+2)

I checked that "srv3" is the primary name by executing the command netdom computername srv3 /ENUMerate:PRIMARY.

"srv1" was listed within alternate names (netdom computername srv3 /ENUMerate:ALTERNATENAMES).

I executed the following command :

    netdom computername srv3 /remove:srv1

and now I'm waiting to see if "srv1" will be registered again.

Does someone know why "srv3" have taken the name of "srv1" in the first place ?