DBCC CheckDB successful but Backup teminates (Msg 3203, Level 16, State 1, Line 3 Read failed: 23)

Following a SAN issue one database was marked Suspect. No other corruption was apparent on any of the system dbs or other user dbs. With CHECKDB showing extensive inconsistencies the recover was restoring from recent .bak & .trn backups. Following the restores CHECKDB across the whole instance was successful and the application was brought back online. However since then the daily backup have continually failed, whilst CHECKDB is always happy across all the whole instance. The Full backups always produce the same error (have also included [b]continue_after_error[/b]) – and always the backup gets to the same point 70% before terminating[color="#FF0000"]Msg 3203, Level 16, State 1, Line 3Read on "mydb.mdf" failed: 23(failed to retrieve text for this error. Reason 15105)Msg 3203, Level 16, State 1, Line 3BACKUP DATABASE is terminating abnormally.[/color] I also see in the System Event log[color="#FF0000"]The device, \Device\Harddisk2\DR2, has a bad block.[/color]The environment is VMWare - Windows Server 2008 R2 SP1 running SQL 2008R2 SP3, Standard Edition and an 11GB database which is separated across 3 files – Primary, Data, Index. The server itself was restarted a couple of days ago to try address the backup issue. SQL Server restarted OK and reports no errors in either the application or system event logs until the backup is tried. Log Backups are being taken and succeed but now there is no valid chain to recover from. The position is worsening with no valid backup now for over a week. Other forums suggest this is due to file access/permissions or disk space for the backup to finish but this is not the case. I’ve considered is detaching/stopping SQL and copying the mdf, ndf, ldf files to another server, but I don't want to stop the system again until I feel more confident with the data being protected. I’m pulling together a process to export all the DB objects and bulk copy all the data out into another database.If the problem is with the Primary file (mdf) why is the CHECKDB not picking it up? I would welcome any thoughts, further checks I could run to help identify what is wrong with this data file and if there any workarounds to get the backups working.Cheers Unsy.