Might be an issue (SoCal ?) in your area.   I suspect that being near the interstates may not help - esp in urban areas.

1. was actually told the opposite, the interstates are covered nationwide.

I am also having connection issues too while on the freeway even with 5G and unlimited data.  It show no network/ poor connection when commuting and no connection even at home.

Today I spend half the day at the t-mobile store and on customer care calls, they reset my network and got me a brand new sim card. I have no network for 3 hours when I return home. now it back to 4 bars then 0 bars.  A family member on the same plan who lives 8 hours away show 1 bar/poor signal all day. I am annoyed as well because it so random.

Interstates are ‘covered’, and typically have good service, IMHO.  I have had some apps (TuneIn) with live streaming often end up in ‘buffering’ even when I’m ~300’ from a site, getting speed tests of +1200Mbps.  Some apps are bad, others are not.  For issues, I was more referring to the Tmobile home internet device, as it comes with ‘deprioritization’.  This can affect your device itself, depending on what plan you’re on.  Since its affecting your speedtest.net performance, I’d check at a local store (assuming you can find one in your travels that isn’t far off the interstate) and test at a store.

I haven’t personally hit this issue myself, outside of some streaming apps that don’t have any buffer (30 seconds) built in.

Oh OK understood.  Unfortunately, customer service for the home internet will not help me.  According to them, the device is supposed to be at my home address, not roaming the country in my truck.  If you ask the store employees, they sell is as a “way better hotspot thats unlimited.”  I just realized as well, how did you know I was in SoCal the other day.

As expected, everything has been great in Washington and now Oregon.  I need to start writing down where the bad spots are so that I can avoid.

Yeah .. devil’s in the details.  Mine was cheap enough ($25/month) that I’ll probably dump Spectrum in a bit.  I’ve kicked them down to the cheapest plan I can get - keep it for backup for work reasons.

Reps did state that I could ‘try’ my home internet connection at a different address, but I think they have certain network tags set up for routing of traffic (QoS tags for prioritization).  This may be what’s killing it.

I had the older 4G LTE home internet (with battery power!) and it worked pretty much like a hot spot.

I-5/10/40 are all down here in SoCal.  5/80/84 are up in Sacramento/Tahoe

As far as using handset .. I haven’t had issues with speed.  ~500Mbs to almost 2Gbps, and haven’t been hit with limits.  T-Mobile service isn’t consistent speeds especially rural.  Even crossing Florida in the spring, it was anything from ‘great’ to buffering on the interstates.  Some highways have improved (CA-126)