SDC2130: Strange encoder feedback

Dear all,

I have the sdc2130 unit connected to a DC motor rated at 3000 rpm and an AMT102-V encoder configured at 2048 ppr.
In closed loop speed the motor runs smoothly, however at a certain speed (approximatly 800 rpm) the encoder feedback turns negative and decreases. And the motor goes rapidly backwards and forwards and then it stops (because of the loop error detection).

I enclosed the chart for the tests we did in open-loop.

After reading the SDC2130's datasheet I thought that the problem was the encoder pin frequency, so I changed the PPR in the encoder to 125 PPR. The problem persists. I already updated the firmware of the unit.

What should I do?

Sorry for the delay,

I've attached the logs that I've done with the unit with the values requested.

Thank you in advance,

I am using the SDC2130 with 2048 PPR encoder.

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