I disagree with part of the answer given by VU2NHW:
In your case, the issue & onus lies upon the manufacturer of the equipment experiencing interference.
This is not what the FCC regulations say (assuming we are talking about US jurisdiction). Part 15 clearly puts the issue in the hands of the consumer. The only recourse the consumer has with the manufacturer is through tort law, not federal regulations. However, the consumer can use part 15 to help qualify them as an aggrieved party to allow tort proceedings if the consumer chooses to pursue this course.
There is also case law that reasonably blocks a neighbor ftom attempting tort actions against the ham. This may not stop a filing necessarily, but it should normally bring the matter to a swift and favorable conclusion for the ham.
In these situations of neighbor complaints, the ham is advised to make sure their signal is clean (spectrum analyzer screen shots) and that they have conducted and logged any necessary RF exposure assessments. Keeping a basic log showing the time going on and off the air, the band, mode, and output power is also helpful. If the FCC then makes an inquiry, the ham can show sound due diligence and will be exonerated by the FCC. The FCC will then send a brochure and letter to the consumer advising them that the ham is operating legally and the problem is with the consumer's electronics.
We all want to be good neighbors and help them with their interference problems. But before getting out your toroids and tools, carefully consider the litigious conditions that surround us and weigh this in your decision as to what course of action you will take.
Computer speakers are notorious for being affected by nearby EM energy. The most effective remediation is the application of toroid cores on the speaker and power leads to the speaker boxes. Depending on the length of the wires, a toroid on each end of the wire may be warranted. Toroid cores of type 31 material are generally the most effective. Get large enough cores to allow connectors to pass through the hole in the center. Make multiple turns of cable on each core as the EM choking goes up as the number of turns squared.