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='68475' and id < 4421179 and id<>'4421179' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='68475' and id > 4421179 and id<>'4421179' order by id asc limit 5