>     Hope you're having a good day, All.
>     there is a problem with %subj%. It plays high frequencies very bad and 
>     dirty. I thought that heads became dirty and magnetic, so, I've 
>     cleaned them up and demagnetized, but it didn't help me! ;(
>     what is the problem?
Do you have the Dolby switch turned on?
It is frequently labeled:
"Dolby"  "DB"  "DNR"  ( Dolby Noise Reduction )
Dolby noise reduction is a two way process.  As the tape is recorded, 
the high-frequencies are emphasized with a special circuit.
During playback, they are un-emphasized - reducing the high-frequency 
hiss of the tape.
There is not a straight one-to-one coorelation, you cannot simply 
cut the treble of your amp to correct for this.
If you are playing a tape that has been recorded with Dolby noise 
reduction, you will need to turn this switch on otherwise, you will 
get the high frequencys you talk about.
Good luck!
--- Via Silver Xpress V4.4 [Reg]
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