Aqui estão vários links para fabricantes e vendedores de mp4. Muitos deles disponibilizam firmwares para download. Estes são alguns dos sites que eu já visitei à procura de fw. Divirtam-se! ;-)

S1 Mp3 Player Firmware Downloads Base!  http://www.s1fw.com/ - Este link é novo, encontrei no site mympxplayer.org, tem muitos firmwares.

www.chinc.cn

www.ann11.com
www.atmt.co.uk
www.apachi.com.cn
www.ipodigi.com
www.i-de.cn
www.aocos.com
www.ainol.com
www.i-sky.net.cn
www.soundera.net
www.iriverchina.com
www.adlo.net
www.aigo.com.cn
www.iver.com.cn
www.cn.aiwa.com
www.ailidian.cn
www.aneca-digital.com
www.iaudio.com.cn
www.sonken.com
www.aishon.com
www.onda.cn
www.allok.com.cn
www.aokl.cn
www.aukmei.com
www.aomg.com.cn
www.ottosz.com
www.OWLMP3.COM
www.kaiyin.net
www.benq.com.cn
www.beto.cn
www.biwin.com.cn
www.it8.com.cn
www.acorp.net.cn
www.bes-china.com
www.boke.net.cn
www.szbeall.com
www.szbeige.com
www.belin.com.cn
www.chuangke.net
www.hkbeond.com
www.bestir.cn
www.szbroad.com
www.bosea.com
www.boyinmp3.com
www.borya.cn
www.eebbk.com
www.cecv.cn
www.cvc-cn.com
www.sealand-china.com
www.greatwall.com.cn
www.cellulartop.com
www.g-phoenix.com
www.odmplayer.com
www.hk-onki.com
www.chinc.cn
www.chuangke.net
www.cn.creative.com
www.created.com.cn
www.digilife.com.cn
www.bjdnc.com
www.szbroad.com
www.zinomp3.com
www.onda.cn
www.szdaoqin.com
www.degen.com.cn
www.theasy.com
www.dcdzc.com
www.dudump3.com
www.stdupont.net.cn
www.deluxmarket.com
www.eqq.com.cn
www.ez-av.com
www.ennyah.com.cn
www.foundertech.com
www.fountel.com
www.fgsz.com
www.philips.com.cn
www.scudcn.com
www.szfysm.com
www.pcflorens.com
www.gold-mine.com.cn
www.gkcyber.com
www.go-video.com.cn
www.growise.com.cn
www.gejie.com
www.gemeitech.com
www.geme.com.cn
www.follow-me.com.cn
www.goldjoin.cn
www.huu.com.cn
www.hacha.cn
www.cyber-hisense.com
www.haixuntech.com
www.0755mp4.com
www.22b324.com
www.v2vw.com
www.besta.com.cn
www.hendon.cn
www.maxstation.com.cn
www.hnsat.com
www.aple.com.cn
www.szhrd.net
www.hytechno.com
www.huboy.com
www.szhk.com.cn
www.rtlchina.com
www.avlinkusa.com
www.hyamp3.com
www.innov-tec.com
www.hymp4.com
www.sz-htx.com
www.e-huashun.com
cn.perceptiondigital.com
www.hyuaui.com.cn
www.icooldigital.com
www.ilyn.com.cn
www.jnc-digital.com
www.luckystar.com.cn
www.mde.cn
www.ezmax-cn.com
www.longkom.net
www.jobon.net
www.giec.cn
www.biwin.cn
www.geil.com.cn
www.keepolo.cn
www.szhaichuang.com
www.k-link.net.cn
www.aple.com.cn
www.szjqsm.com
www.winward.com.cn
www.jsa.com.cn
www.jinxing-digital.com
www.goldyip-cn.com
www.jwdigital.com.cn
www.kpm.com.cn
www.jren.com.cn
www.hengxinkeji.com.cn
www.ivory.net.cn
www.kissdp.com
www.knc-digit.com
www.coupesz.com
www.kegutech.com
www.fangke-model.com
www.sz-keneng.com
www.koky.com.cn
www.szksm.com
www.kwss.com.cn
www.szkewei.com
www.keyingmp3.com
www.kocode.com
www.canyon-tech.com
www.51cube.com
www.coodoo.com.cn
www.szkuer.com
www.lg.com.cn
www.digitalbhb.com
www.ramos.com.cn
www.lensun.cn
www.netac.com.cn
www.langyoudz.com
www.radiosz.com
www.lovont.com
www.gzlezhi.com
www.luxpro.cn
www.szvision.net
www.szlizhong.cn
www.ldxmp3.com
www.lptmemory.com
www.lenovo.cn
www.aocdigi.com
www.ileawin.com
www.travelstar.cn
www.mpeye.co.kr
www.moosik.biz
www.good110.com/meeto
www.my3ia.com
www.kva.cn
www.rtlchina.com
www.mpio-digitalway.com.cn
www.szyopo.cn
www.melda.cn
www.meizu.com
www.ujaa.com
www.wewa.com.cn
www.musekj.cn
www.minbo.net
www.benq.com.cn
www.iq168.com

www.numberone.net.cn
www.usb-mp3.com
www.nuojie.cn
www.oppo.com
www.orpha.com.cn
www.ocsuny.com
www.my3ia.com
www.popspa.com
www.pengfa.net
www.apple.com.cn
www.idop.cn
www.szfront.cn
www.poozi.com
www.mymarvel.com
www.hedigi.com
www.qixiangtech.com
www.apod.com.cn
www.thtf.com.cnwww.szthtf.com
www.62792288.com
www.hussar.net
www.rec.com.cn
www.ergotech.com.cn
www.rsdsm.com
www.retop.com.cn
www.rbnmp3.com
www.easuco.com
www.soul.com.hk
www.irain.com
www.aieyuel.com
www.yepp.com.cn
www.sundisk-it.com
www.sunkey.cn
www.sankas.com
www.sunin.cn
www.hyuaui.com.cn
www.times168.com
www.tech-cdt.com
www.21sjhy.com
www.sz-suno.com

www.sonk.cn
www.matsunichi.com.cn
www.panasonic.com.cn
www.suang.cn
www.socany.com.cn
www.sogood-cn.com
www.sony.com.cn
www.tcl-vg.com
www.taiyanfa.com
www.teclast.com
www.wistarmedia.com/thomson
www.tms-cn.com
www.citso.com
www.topluxdigital.com
www.coyo.net.cn
www.sztingchao.com
www.wewa.com.cn
www.msc.cnwww.mscmp3.com
www.worthy.com.cn
www.szwjsm.com
www.wellsound.com.cn
www.szmicrotech.com
www.wemo.com.cn
www.microstar.com.cn
www.xyhc.com.cn
www.si-bay.com
www.syscanscky.com
www.amoi.com.cn
www.hyundai-mp3.com.cn
www.sunwoods.net
www.chiprise.com
www.xinvo.com
www.newxye.com
www.shinco.com
www.xinlan.com.cn
www.iboin.com
www.909sd.com
www.xhy168.com
www.vanhe.com
www.truly-cn.com
www.sungworld.com
www.xundu.com
www.usboem.com
www.asion-tech.com
www.yongmp3.com
www.eaget.com.cn
www.sztym.com.cn
www.hua-sun.com
www.szyinhu.com
www.mingweilong.com/diyhp/30690/zhch/home.html
www.yinlips.com
www.yeston.net
www.pc100.cn
www.unibit.com.cn
www.ugee.com.cn
www.window88.com
www.zino.net.cn
www.zarvadigital.com
www.szzhenhai.com
WWW.ZLEND.COM.CN
www.zsctc.com
www.zdxmp4.com
www.digilife.com.cn
www.dcdzc.com
www.cntek.net
www.chino-e.com
www.szziming.com