DSLwifi gateway, streaming, downloading etc is extremely slow, none stop buffer'n, then will just black out.

Dsl gateway worked great, installed 3ish months ago. Working as expected. Had the same service at our prior house and never had a problem with uploading downloading streaming playing games even though we're on a low plan it's still worked out fine. Since we moved here it's worked out until now it doesn't work, It's so bad we can't even use it. I may want to mention that I was trying to hook up my Google camera in the backyard and it suggested to do some changes on the interface of the modem the Gateway and I did you a few minor tinkerings and I may have messed something up I don't know it may be that or may not be I don't know but it's just crap now could you please help?