That is annoying. Which modem are you using at the moment ?
I'm still with the HG612 at the moment.
I had a DLM resync though shortly after, and I can see in the telnet stats that upstream FEC errors are showing, so maybe G. Inp is switched on upstream.
There's obviously external rfi somewhere
However it seems to have fully recovered now. I also switched off to pop in my cat6 modem lead, gained me a slight sync increase it seems.