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Pete, Engineer
Category: Electronic Musical Instruments
Satisfied Customers: 29371
Experience:  Over 20 years of experience in the Electronics and IT industries.
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I bought a roland ac 40 last year and tonight when I played

Customer Question

I bought a roland ac 40 last year and tonight when I played it started making a noise like a food mixer then produced a constant high pitched noise
JA: How long has this been going on with your Roland? What have you tried so far?
Customer: it just started tonight. I just switched it off
JA: Anything else you want the Phone Expert to know before I connect you?
Customer: no thank you
Submitted: 2 years ago.
Category: Electronic Musical Instruments
Customer: replied 2 years ago.
I switched it off for a while and it now seems to be working normally
Expert:  Nicola-mod replied 2 years ago.
I've been working hard to find a Professional to assist you with your question, but sometimes finding the right Professional can take a little longer than expected.
I wonder whether you're ok with continuing to wait for an answer. If you are, please let me know and I will continue my search. If not, feel free to let me know and I will cancel this question for you.
Thank you!
Expert:  Pete replied 2 years ago.


Try disconnecting everything except the power cable from the amp, then turn it on again.

Let me know if it still whistles, or if it only whistles when you have a guitar or other instrument attached to it.