变压器运行时出现声音异常的原因主要有（ ）。

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='68478' and id < 4421431 and id<>'4421431' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='68478' and id > 4421431 and id<>'4421431' order by id asc limit 5