Dump database to disk

I have created a dump device within my Sybase 11.92 db to point to a Disk Drive.

When I try to 'dump database master to "diskdump"' , the dump appears to hang at
"WARNING: In order to LOAD the master database, the SQL Server must run in
single-user mode. If the master database dump uses multiple volumes, you must
execute sp_volchanged on another SQL Server at LOAD time in order to signal
volume changes.
Backup Server session id is: 44. Use this value when executing the
'sp_volchanged' system stored procedure after fulfilling any volume change
request from the Backup Server.
Backup Server: 6.52.1.1: OPERATOR: Volume to be overwritten on
'/dbdump/Master_dmp/master' has unrecognized label data.
Backup Server: 6.78.1.1: EXECUTE sp_volchanged
@session_id = 44,
@devname =
'/dbdump/Master_dmp/master',
@action = { 'PROCEED' | 'RETRY' | 'ABORT' },

@vname = <new_volume_name>:


When I use the same command to tape it runs smoothly. What's up? Thanks in advance.