Posts: 280
Threads: 38
Joined: Jan 1970
Did you try a MEMORY LOST?
Did you remove battery too?
Where do you live? In France or Canada?
Posts: 115
Threads: 10
Joined: Aug 2008
If you have CF 26 and then BEEP it do not think it will help as that makes the HP41 silent. Any BEEP or TONE that will make a sound (SF 26 first) should make the high pitched sound go away.
The high pitched sound is usually the result of garbage (non-zero) in the internal T register which used for making sound. Any normal beep/tone will put 0 in T when done.
If that does not help, then you probably have a hardware problem. Some remove battery battery trick might help, if you are lucky.