Can't find process that is creating backups
2015-09-03 19:02:30.71 Backup      Database backed up. Database:
  db_name, creation date(time): 2012/10/12(20:52:11), pages dumped:
  3290021, first LSN: 276028:152755:172, last LSN: 276028:152827:1,
  number of dump devices: 1, device information: (FILE=1,
  TYPE=VIRTUAL_DEVICE: {'{95380B0A-D50B-408F-B95F-1AB8975BA7F8}5'}).
  This is an informational message only. No user action is required.


The fact that VIRTUAL_DEVICE comes into the backup message clearly says that this is not backup scheduled by T-SQL Job or SQL Server so you wont find it anywhere in SQL Server. You either have some third party tool or windows inbuilt backup mechanism running which is taking this backup. 

Now if you really want to find out the source of backup consult windows team or storage team and you would get a fair idea. If all the stakeholders say they do not have idea about the source of backup ( which is highly unlikely) you can stop such backup from happening by disabling SQL Server VSS writer from Services.msc. 

Such Third party backups rely on SQL Server VSS writer services to connect to database and take backup.

Before proceeding above I would suggest you to talk to backup/windows admin if they are not aware about any such backup you can go ahead and disable this service. Otherwise you must not and you should consult more regarding this with them.

Please read Information Shedding Light on VSS Backups