Restic check + Rclone constantly packet timeouts

I am using restic 0.9.5 compiled with go1.12.4 on linux/amd64

Describe the issue

The problem might be identified just in RCLONE but probably in the common set-up of both components. I am using rclone to backup my data with pCLoud via API service. This is working fine. The problems have been seen in the backup process:

restic -r rclone:pcloud:Backup/Restic/Test1  backup  /  \
        --verbose \
        --exclude-file=/etc/restic/backup-exclude.conf  \
        --cleanup-cache \
        --exclude-caches \
        --one-file-system

Creating incremental backup …
open repository
repository b3614e88 opened successfully, password is correct
lock repository
load index files
using parent snapshot 0c5c5488
start scan on [/]
start backup on [/]
scan finished in 17.311s: 136381 files, 9.568 GiB

rclone output:

2019/08/11 11:07:19 ERROR : data/87/873910db86cfa9e11b2f8bc23aceac92869cdb64f0d72ef32a8b2d9bb870b673: Post request put error: Put https://api.pcloud.com/uploadfile?filename=873910db86cfa9e11b2f8bc23aceac92869cdb64f0d72ef32a8b2d9bb870b673&folderid=3946464745&mtime=1565514136&nopartial=1: read tcp x.x.x.x:51254->y.y.y.y:443: i/o timeout

The following lines are just repeating the above error output.

restic forget \
        --prune \
        --keep-last 7 \
        --keep-daily 14 \
        --keep-weekly 4 \
        --keep-monthly 6

restic check

After restic check a lot of IO errors ans unexpected EOF came up:

pack file cannot be listed 2e24847b2f4adcdacc941c07430ada6cba026991f96ab9a3d495a85e2dfb4c94: unexpected EOF
rclone: 2019/08/11 11:44:57 ERROR : data/3c/3c3f9668fed4d32985e274b02bc5a76c3a7f5b41fc9fc719c3b2544fcdc1e2c6: Didn't finish writing GET request (wrote 40960/42068 bytes): read tcp x.x.x.x:59630->y.y.y.y:443: i/o timeout
Load(<data/3c3f9668fe>, 42068, 4216094) returned error, retrying after 419.340488ms: unexpected EOF

The following lines are just repeating the above error output.

I already checked with native rclone read operations:

rclone ls pcloud:Backup/Restic/Test1/snapshots:

  302 0c5c5488e1d18f1bb4053fae9b1ce230b3c54c2e525296933ab5819f43957b9c
  379 14a1e04fc931b2f1e37a8c4b52ea143f01a5d0c577481da9b1ddf03e5695f5c0
  302 25c3eab0023fd6973d1f533bc8177665ae8a93eec0d547270660ea785a34767e

rclone ls pcloud:Backup/Restic/Test1/data/ :

4327178 91/91a696950fc709d51e87f4e85f6022d6343539c1c12557c485dd57097b044e77
4537483 91/91c7b8898593c8ba94b99ca99f3d629f18d9ce5e79a9c7c2123e73be9ad6242f

Additionally I have been tested a with a native RCLONE upload using a huge file of 12 GB:

rclone copy file.bin pcloud:Backup/Restic/Test1 --progress --stats-unit bits

Transferred:       11.906G / 11.906 GBytes, 100%, 72.529 MBits/s, ETA 0s
Errors:                 0
Checks:                 0 / 0, -
Transferred:            1 / 1, 100%
Elapsed time:    22m24.7s

Finally the upload was possible without any problems !!

Why is native RCLONE copy working while RESTIC + RCLONE have these difficulties???