Is 10-11 mb/s data transfer speed to be expected from the 1TB Time Capsule A1355?

You should get 40-50MBytes/s transfer speeds over ethernet.

So first question.. b is bits and B is Bytes.. lets be clear what you are measuring and how.. network speed is in bits per sec. File transfer is in Bytes per sec just to be confusing.

10-11MBytes/s sounds like you have a 100mbit limit in there somewhere. Most TV and video players only use 100mbit ports.. that = 12MBytes max.

And is more than fast enough for any HD video.

So second question.. what are you playing the videos on.. and is it 100mbit ports.. there is the throttle.. but it should not cause issues.

If you are using windows.. it can be slow.. to windows the TC is an NT server.. and it is less than excellent..

Give me a straight file copy speed from your computer to TC with wireless off.. use a single large file.. eg >1GB and tell me what you get.

Copy the same file back to the PC.. tell me what you get.

10.7MB/s sounds to close to 100mbit to be coincidence.

Find out if gigabit is really linking at gigabit.

If you have wireless on.. turn it off.

If you have ipv6 off turn it on.

Any mac that runs 10.4 might have IDE disk that is so slow it is unable to manage even close to gigabit speed.

Over wireless you will never really get high speed, and wireless will interfere with ethernet.. for reasons even I do not understand.. so make sure it is off.

Try again..

I have tested it from windows xp up to 8.1 and have no problems but you must be running everything exactly right.

Windows will have much more issues than Mac getting the connection to full speed.

Let me modify my statement above.. on a good day.. when everything in windows is running just right.. it is fine..

Today.. my copy to the TC managed a peak of around 12MB/s and copy from the TC was around 18MB/s

The same file copied to a 2011 mini.

And from the mini back to the TC.

So windows is doing its usual stuff.

Test windows in isolation from the network.. so just ethernet from LAN TC to LAN windows PC..

Tell me what speed you get.. do you have IPv6 on?? This is now important.

To make sure everything is ok.. I also run a Synology NAS..

The PC can manage 115MB/s to it..

The Mac..

Writes at 95MB/s and reads at 115MB/s

Try a few different settings.. my TC is an old Gen1 so it is a bit older and slower than Gen3.

Is your homegroup turned on?

Is the firewall off? Is the internet set to private?

Did this problem become worse at win10 or was the same at win8??

You can see why it is better NOT to use TC as a NAS.. buy a proper NAS.. QNAP or Synology.. it will completely flatten the TC.