How do I fix high frequency hum in 4-track cassette recorder...?

Hey everyone,

I have a Vesta Fire MR-10 (4-track cassette recorder). Purchased maybe 6 years ago, worked perfectly. Now the whole the right channel (on line ins/outs and tracks 2 and 4) has a completely unusable "whine" or almost sine-waveish static tone at around 4.5kHz.

I've attached an image from a spectrum analyzer of the machine as well as a short clip of the noise.

Channel 1 and 3 are clean and fine, no issues, but when using track 2 and 4 or using the right channel at all I have this issue. It is the unit and not my tapes.

Anyone have any ideas what might be going wrong?

Thanks!









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Attached Files



VestaFire_RightChannelFreqHum.mp3 (390.8 KB)