I called TP-Link's call center for support today. The answer I got was that I should try plugging the modem into someone else's line and test. They said they couldn't do anything until I did that. That answer seemed like a joke. 

972 errors in 4 minutes with a single device connected?

  @Joseph-TP 

Although not entirely, but yes, it seems so,

The web admin interface in the browser sometimes lags, sometimes requiring me to re-enter my password. When I log in to the TP-Link Tether app, it asks for confirmation on the password screen (sometimes it says the connection to the device is not established), and in the app interface, I get an error saying there's no internet connection, forcing me to exit and re-enter the app. (PS:But I can use Tether app with Archer c80 rooter without any problems while the modem provided by the ISP is in bridge mode.) The wireless/DSL lights remain on, but I sometimes experience momentary lags in the web browser and YouTube videos. These are my observations so far.

I'll be running speed tests with this modem over the wired connection compared to my previous modem.

Hello  @Joseph-TP 

First network diagram:
modem (ISP modem: TD-W9970 v3) in bridge mode + Archer c80 (stands for wired connection as router mode)  ((wired&wireless client devices = No Error
Second  network diagram:
Only VR600 V3 ((wired&wireless client devices = dozens, hundreds, sometimes thousands of Errors appearing at once!

Current Rate (kbps) of ISP modem on Downstream is 51176 but Archer VR600's 51199. Archer VR600 has Errors (pkts) on only Downstream.
Both of them have the same Upstream Current Rate (kbps) (15356) There are no Errors (pkts) in Upstreams. I wonder if this could be related to Current Rate (kbps) on Downstream? 

ISP:TURK TELEKOM (TTNET)_VDSL

I've modified modem MAC adress, MTU size (1492), Authentication Type:PAP

55 errors in 8 hours of use, 10 errors in half an hour of use so far. All of these errors are, of course, on the downstream side.

The number of errors can suddenly reach four digits. This is really frustrating!

Also tried to enable SRA, it doesn't actually work.

I don't understand how the SNR margin on the ISP-provided modem is around 15, but it drops so much on the VR600. Furthermore, there are no logs for those errors. I'm stuck at this point.

Up up!

Hello  @Joseph-TP 

I suspect the downstream errors are common, as friends of mine who use this product and other models (VR2100, TD-W9970) are experiencing the same issue. I couldn't get a solution either. I had to return the TP Archer VR600 on Friday.